CONTRACTOR REPORT SAND83 - 7028 Unlimited Release UC-63a Modular Photovoltaic Array Field Hughes Aircraft Company P.O. Box 9399 Long Beach, California 90810-0399 Prepared by Sandia National Laboratories Albuquerque, New Mexico 87185 and Livermore, California 94550 for the United States Department of Energy under Contract DE-AC04-76DP00789 Printed September 1984
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Hughes Aircraft CompanyP.O. Box 9399Long Beach, California 90810-0399
Prepared by Sandia National Laboratories Albuquerque, New Mexico 87185and Livermore, California 94550 for the United States Department of Energyunder Contract DE-AC04-76DP00789
Printed September 1984
Issued by Sandia National Laboratories, operated for the United StatesDepartment of Energy by Sandia Corporation.NOTICE: This report was prepared as an account of work sponsored by anagency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of theircontractors, subcontractors, or their employees. makes any warranty, ex~
press or implied, or assumes any legal liability or responsibility for theaccuracy, completeness, or usefulness of any information, apparatus, product' or process discloeed, or represente that ita use would not infringeprivately owned rights. Reference herein to any specific commercial product,process, or service by trade name, trademark, manufacturer, or otherwise,does not necessarily constitute or imply ita endorsement, recommendation,or favoring by the United States Government, any agency thereof or any oftheir contractors or subcontractors. The views and opinions expressed herein do not necessarily state or reflect those of the United States Government,any agency thereof or any of their contractors or subcontractors.
Printed in the United States of AmericaAvailable fromNational Technical Information ServiceU.S. Department of Commerce5285 Port lWyal RoadSpringfield, VA 22161
AbstractThis final report describes the procurement, fabrication, assembly, installation, and test of a fixedflat-panel photovoltaic (PV) array field composed of modular 10 kWp building blocks. Implementation of this hardware program was in strict adherence to the designs developed under a priorSandia contract for an array field optimization and modularity study for intermediate power (20to 500 kW) size systems. The basic objective of this program is to verify the balance of systemscosts developed under the prior study contract. Each of these modular building blocks of anominal 10 kWp was installed at the Photovoltaic Test Facility of Sandia National Laboratories,Albuquerque, New Mexico. Major features of the balance of systems incorporated ± 200 Vdcbipolar circuitry, a low cost hybrid structure/foundation featuring a frameless panel and selfgrounding foundation, and a power collection center for housing the modular system controls andprotection circuits. An economic analysis of the completed project showed that the objective wasrealized for achieving an installed, low-cost balance of systems for an intermediate power, flatpanel photovoltaic array field.
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v-vi
PAGES iii & lv ARE BLANK
MPAF FINAL REPORT
TABLE OF CONTENTS
SECTION PAGE
1.0
2.0
Introduct ion l) ••••••••••••••• .: ••
Design
1
3
Installation , .
Procurement ' .
Checkout, Test, and Evaluation ••.•.....•••••.•..••••••.
Array Wiring •••••••••••••• '.••••••••••••••••••
336
7
77
10
10101011
11
11
14141417
17
172626
Intermodule Wiring .•.•.•••••..•.•••Field Cabling and J-Boxes ..••.•.••.Power Control Module ••.•••••••••••.Power Collection Center ••••••••••••
Photovoltaics .•....•.....•..•................J-Boxes and Cabling ..••...•.•..•.••..••••..••Power Collection Center .••••••••..••.•.••••.•
Module Matching .•••..•.••.•.••..•••.•.•••..••Panel and J-Box Installation •••••••••••••••••
3.3.13.3.23.3.33.3.4
Site Preparation and Foundations •••.••••••.••Cabling, Counterpoise, and Power CollectionCenter ' .
Assembled Panel Being Moved to Structures •.•••.•••..•••
Panel Assembly to Stanchions •.•••••••••...•.•.•.••••.•.
.................... 0, •••••••••••••••••
4
5
12
15
16
18
19
20
21
PAGETITLE
•••••••••••••••• II ••••••••••••••••••Module Matching Plan
Solarlok Connector
FIGURE
2.1-1
2.2-2
3.3.4-1
4.2-1
4.3-1
4.4-1
4.4-2
4.4-3
4.5-1
TABLE
5.5-1
6.0-1
LIST OF TABLES
TITLE
Photovoltaic Array Electrical Performance
Material and Subcontract Procurement .•••.••..••••.•.•••
PAGE
24-25
28
APPENDICES
A Solar Cell Module Product Specification
B
C
General Contractor Statement of Work
Block IV Test Data
D
E
Environmental Test Reports
Hot Spot Endurance Test Report
ix-X
-Preceding page blank
ACKNOWLEDGEMENT
This procurement and installation of the Modular Photovo1taic ArrayField (MPAF) was conducted by Hughes Aircraft Company with George J. Naffserving as Program Manager and Leo A. Shi110ng as Project Engineer.The very able assistance of Mr. Sid Johnston of Sandia Laboratories isgratefully acknO\'11edged and deeply appreciat,ed. Also acknowledged anddeeply appreciated are the contributions of the following participants:
Hughes Aircraft Company
Solarex Corp.
Abbott MechanicalContractors, Inc.
N. MarshallM. Van LeeuwenD. CohenN. ChaseJ. CastleJ. Wi '11 i amsonY. HOI"ning
J. HOI~l scher
F. Abbott
xi-xii-~..-_..---
Preceding page blank
FINAL REPORT
MODULAR PHOTOVOLTAIC ARRAY FIELD
1.0 INTRODUCTIONIf the creation of a viable industrial and commercial market is to beachieved, reducing photovoltaic (PV) system costs is essential.
One approach to reduce the system costs is dE~veloping a standard arrayfield building block that either alone or in multiples satisfies asubstantial portion of the intermediate sector needs. This strategywould greatly reduce site specific design work. Also, including
innovative installation and fabrication techniques, and low coststructures and optimized field wiring designs, would signficantly
reduce overall system costs.
Under Sandia Contract No. 62-9188, the Hughes Aircraft Company hasconducted an Array Field Optimization and Modularity (AFOM) Study
(Ref. 1) to develop optimum designs of PV array fields and a modulararray field building block. Under Sandia Contract No. 68-3152, Hughesfabricated, assembled, installed, tested, and put into operation aModular Photovoltaic Array Field (MPAF) based on the modular buildingblock design of the AFOM project. This array, composed of threemodular 10 kW array field building blocks, was installed at thePhotovoltaic Test Facility at Sandia Nationa"1 Laboratories andinterfaced with the Sandia provided power conditioning system and load.
The prime objective of this program was to fabricate and install the
MPAF that will act as a test bed, allowing Sandia to evaluate thefindings of the AFOM study program, including array field
characteristics, design/component reliability, durability, and,particularly, the Balance of System (BOS) cost projections.
-1-
The array field modular building block was designed as a ~ 200 Vdc
bipolar unit with a nominal power rating of 10 kW. The building blockconsists of two 200 Vdc monopolar subarrays oriented in an east-west
row. Each building block array structure is 160 ft long andaccommodates 40 PV Panels, each panel containing four 2 ft by 4 ft PV
modules. The panels are secured at the appropriate tilt angle to afront and rear row hybrid foundation. The front row foundation is a
buried metal foot structure that acts as a buried ground counterpoiseand is an integral part of a grounding net. The rear row foundation isa concrete curb designed to withstand the priamry wind lifting forces.
Power from each building block is routed from the junction box to aPower Collection Center (PCC) via direct burial cable. The PCC
contains circuit breakers, bus bars, and Power Control Modules (PCMs)each capable of servicing two building blocks; thus, the field is
sectionalized from a control standpoint in 20 kW increments.
Procurement of hardware adhered strictly to the design developed underthe AFOM program. The selected PV module configuration was
qualification tested to ensure trouble free service over the projectedtwenty year life. To assist in the site preparation and installation,
Hughes obtained the services of a general contractor from theAlbuquerque area. The system was installed and checked out on site by
both Hughes and the general contractor. The system performed asdesigned and, following final testing, was accepted by Sandia on 25
February 1983.
When the differences between the AFOM assumptions and the MPAF lI one-ofa kind ll procurement are considered, the BOS costs compare very
favorably with those developed under the AFOM design study. The BOScosts are no longer a major concern in making photovoltaic power
affordable.
-2-
2.0 DESIGN
2.1 STRUCTURAL
The structure/foundation configuration utilized in the Sandia array isdescribed in Section 4.2.2.4 (page 4-16) of Ref. 1. A typical segmentof this assembly is depicted in Figure 2.1-1.
The structural members were brake formed from low carbon sheet steelmaterial and hot dip galvanized per the specifications of the ASTMA527. The benefits of this structural system include its excellentcorrosion resistance and its economy of fabrication. This economyresults from the efficiency of specifying wall thickness proportionalto each member1s load requirements, the ability to punch holes
economically into the flat stock prior to forming, and the low cost ofthe raw sheet material.
Fasteners joining the aluminum PV module frames to the galvanized panelframes are stainless steel to preclude potential dissimilar metalcorrosion. Because zinc is compatible with aluminum, galvaniccorrosion does not exist at the junctions of the panel and moduleframes. Other fasteners joining the structures are protected fromcorrosion by cadmium or zinc plating.
2.2 PHOTOVOLTAIC (PV) ARRAYThe basic PV constituent is the 5.2 Vdc, 66 watt, 2 ft x 4 ft solarcell module described in Hughes Procurement Specification SEP-11387(Appendix A). Forty of these modules are series connected in a foldedconfiguration (twenty modules per row) to form one string. Two stringsare connected in parallel to form a pole. Two poles (positive andnegative) form a ! 200 Vdc, nominal 10 kW building block. A buildingblock is represented by one of the three rows shown in Figure 2.2-2.To achieve the nominal 30 kW system; three of these building blockswere installed. Modules are interconnected using Amp Solarlok
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connectors. A junction box was located at the inner end (center) of
each pole for collecting PV power.
2.3 ELECTRICALThe electrical design of the modular 30 kW system incorporated thedesign features contained in Reference·1. The exception was thelightning arrestors, deemed unnecessary because of surrounding
structures.
The major electrical design attributes are incorporated to:(a) Prevent injury to personnel.(b) Prevent or minimize damage to equipment.(c) Minimize the effect of disturbance upon the uninterrupted
portion of the array field, both in extent and duration.(d) Minimize unwanted interaction with the interacting power
system.(e) Provide the requisite level of protection at minimal life
cycle energy costs.(f) Achieve modular expandability in a cost effective manner.
Choosing bipolar electrical distribution satisfied the aboveconsiderations. Bipolar distribution offers lower stress voltages tothe dielectric materials used in the system, and also ensures goodground fault protection at the lower line-to-ground potential. Usingvoltage suppression devices and snubbers minimizes any disturbance orinteraction on the lines.
Isolating the system at various points was essential to the safety ofpersonnel and equipment. The Power Collection Center (PCC) ismodularly expandable and can accommodate increases of building blockpower up to 100 kW by merely adding Power Control Modules (PCMs) into
the PCC enclosure. A PCM can handle up to 20 kW. All the electricalhardware was chosen from commercially available products complying withthe local and national electrical codes.
8
3.0 PROCUREMENT
3.1 STRUCTURAL EQUIPMENT
The structural equipment for the PV modules was procured as an opensubcontract solicitation. Shop drawings were prepared, sent to anumber of local Los Angeles and Albuquerque vendors for fixed pricequotations, and the order was placed with the lowest bidder. Because
all the structural members were made to dimensioned drawings, Hughesinspected all parts for conformance and then shipped them to the Sandia
site.
In the interest of shipping efficiency, Hughes initially planned toassembly the PV panels at the Hughes facility; however, PV modules from
the East Coast vendor and the panel structural members from the WestCoast were both shipped directly to Albuquerque. The panel assembly
task was added to the Statement of Work (see Appendix B) to beperformed by the Hughes' general subcontractor installing the array.
Details of this panel assembly are discussed in the installationSection 4.4 of this report.
To effect the installation of the system hardware, Hughes decided tosubcontract this work to a general contractor in the Albuquerque area.Solicitations to bid, along with Statements of Work (see Appendix B),were mailed to four contractors; three bids were received. The bidswere reviewed by a Hughes Source Selection Board composed ofprocurement, pricing analysis, and engineering personnel. AbbottMechanical of Albuquerque, the lowest bidder, was selected by theboard.
3.2 PHOTOVOLTAIC (PV) MODULESHughes prepared a solar cell module product specification (No. SEP11387 inclu~ed in Appendix A) for procuring the PV modules. Requestsfor quotes for these modules were sent to six PV modules manufacturers:
Arco Solar, Solec International, Solarex Inc., Solar Power Corp.,Photowatt Inc., and Motorola. Hughes evaluated the responses for
9
technical acceptability. The final selection of Solarex Inc. was based
on price, delivery, and compliance to the specification.
The specification defines the electrical performance parameters andmechanical design of the module. The specification, conforming toJPL' S Block V solar cell module design and test specification (Ref. 2),defines all the quality assurance provisions which ensure that all
requirements will be met, including acceptance and qualificationtesting.
The qualification test requirements specify five environmental tests
Solarex submitted Block V data (Letter, October 18, 1982 - see AppendixC) qualifying the module by similarity on the latter three tests above.
Full thermal cycle and humidity freeze testing were conducted on theSolarex PV modules by an independent testing laboratory, Litton/Amicon,
to the JPL Block V test specification. The modules satisfactorilypassed these tests (See Appendix D - Environmental Test Report onHughes/Sandia Photovoltaic Modules, December 2, 1982).
Additionally, these modules were subjected to a hot spot endurancetest; the modules successfully passed this test. Appendix E contains
the hot spot endurance test report submitted to Hughes by Solarex.
<
All production lot modules were subjected to acceptance testing. Eachmodule was visibly inspected for any non-conforming or damaged frontsurfaces, frames, solar cells, interconnects, solder joints, laminates,terminals, diodes, and dimensional variations.
10
Each module's electrical performance was determined by obtaining acurrent-voltage (I-V) curve of the module under a pulsed xenon solarsimulator at standard conditions. Each module was sorted into one oftwelve current groups (A through L), based on the I-V curve performancedata.
The performance distribution of the modules procured for thisinstallation is shown below:
Current (Amps) Quantity ofGroup at 5.2 Volts Modules Received
A 11.27 - 11.50 0B 11.50 - 11. 75 aC 11. 75 - 12.00 2D 12.00 - 12.25 6
In addition to electrical performance testing, each module was also
subjected to a 3000 Vdc electrical isolation test and a diodeverification test. All acceptance test data were submitted to Hughesfor review and approval.
A sample of three production modules selected at random by a Hughesrepresentative was sent to Hughes Support Systems, Long Beach forinspection and performance verification. Hughes obtained I-V curvesfor each of the modules under natural sunlight conditions. The datawere corrected to standard conditions of AM 1.5, 1000 W/M2, and 250Ccell temperature. The performance of these modules agreed with
Solarex's acceptance test data within less than + 2 percent.
11
All but the above three mdoules were shipped in plywood, palletized
shipping containers directly from Solarex Inc., Rockville, Maryland toSandia National Laboratories in Albuquerque, New Mexico. The modules
were packaged fourteen to a container, stacked vertically, resting ontheir 4 ft edge, and held in place with a foam separator.
During shipment twelve of the twenty-six containers were turned ontheir sides. Because of inadequate bonding, the foam separators cameloose, and the modules were found lying against one another. Otherthan scratches to the module frames, only two modules appeared to havedamage to the back surface. One had a tear in the tedlar backing,
which was repaired, and the other had small dents. Module performancewas unaffected.
3.3 ELECTRICAL EQUIPMENT
3.3.1 Intermodule WiringFactory fabricated intermodule jumpers of insulated No. 10 AWG wirewith male Solarlok connectors were purchased directly from Amp Inc.
The Solarlok male connectors were compatible with the PV modulereceptacles.
3.3.2 Field Cabling and J-Boxes
The UL listed field cabling was procured to National Electric Code(NEC) Standards for direct burial cable. The J-boxes were outdoor NEMA
3R type fabricated by Pico Metals, Los Angeles. Terminal blocks wereinstalled in the boxes prior to shipping to Sandia.
3.3.3 Power Control Module (PCM)Two PCMs were assembled using commercial electrical components. Thecomponents were mounted on a standard 19 inch RETMA panel. the PCMs
contained the manual crowbar, the blocking diodes, and suppressiondevices. Each PCM can handle up to two 10 kW building blocks.
12
3.3.4 Power Collection Center (PCC)The PCC enclosure (see Figure 3.3.4-1) was fabricated by the Square DCompany, Los Angeles, CA. Square Dwas chosen because its equipmentconforms to the NEC codes and utility standards. The PCC enclosurecollects the power from the array at one centralized control point.The PCC incorporates a NEMA 3R outdoor enclosure and consists of theSquare D I-line breaker switch board terminating in 400 A main lugscapable of handling 2/0 through 500 MCM cable. A rack above the switchboard is used to mount PCMs. The size of the PCC enclosure satisfiesthe modularity requirement by allowing for the installation of multiple(up to five) PCMs. Each PCC enclosure is capable of handling up to teneach 10 kW building blocks. Modularity is maintained beyond tenbUilding blocks by replicating the PCC, one PCC for each additional oneto ten building blocks. The enclosure has two doors, one front and onerear, that can be locked for safety. The front door offers access tothe manual crowbars on the PCM panels and to the disconnect circuitbreakers on the switch board. The rear door opens into the compartmentwhere all input and output cables are terminated.
4.0 INSTALLATION
4.1 SITE PREPARATION AND FOUNDATIONSThe installation site had recently been cleared of asphalt, so siteclearing by Hughes was not required. Major surface unevenness wasrough smoothed with the bucket on the trenching back-hoe, and finalsmoothing was done while back-filling the foundation. The site issloped approximately 1 percent in the east-west direction andapproximately 1.5 percent in the north-south direction. The east-westslope is negligible from an array installation standpoint; the northsouth slope was accommodated by adjusting foundation trench depths.
All the trenches were dug with a back-hoe after the site was surveyedand the trench and PCC Pad locations were marked. A wheel trencher wasoriginally proposed, but the back-hoe provided a smoother trench
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bottom. The trench bottom was covered with an inch of sand to aid intrench foot leveling during the front earth foot/stanchioninstallation.
Pre-assembly of two or three foundation segments along the clear trench
edge during the front foundation installation was soon found to be inefficient due to the cumbersome handling of these assemblies and due to
the inevitable spillage of dirt into the trench during assemblyplacement. Assembling these parts in the trench proved to be moreefficient when performed by a technician seated on the clear trenchedge and bending forward to install the fasteners. After loose
assembly of a row of feet and stanchions (Figure 4.3-1), a string wasstretched along the row of stanchion tops for alignment reference. To
set lateral stanchion spacing, the small alignment angles (Figure 4.31) were bolted across the stanchion tops. The stanchions were then
secured in sequence using the reference string and a level to verifyalignment. The fasteners were then tightened and the trench wasmanually filled to 1/4 depth to secure the stanchion positions.
The secured front stanchions served as the locating fixtures for therear concrete curb stanchions. Rear stanchions were bolted to the
large alingment angles and placed into the concrete curb trench. Thefront ends of the large alignment angles were then bolted to the frontstanchions, and small alginment angles were bolted across the rearstanchions for lateral alignment. With the rear stanchions secured as
described, a concrete ready mix truck was driven down the array rows,and the rear concrete curb trenches were filled with concrete,completing the array foundation installation.
The pee foundation, consisting of a 4 ft x 3 ft concrete pad 4 inchesthick above grade, was simply formed and poured during the array curb
foundation filling. The front stanchion trenches were backfilled, andthe site smoothing was completed after all foundations were in place.
This task was largely accomplished with the back-hoe and finished withshovels and rakes. The site sterilization and gravel application were
accomplished after the system installation was completed.
15
4.2 CABLING, COUNTERPOISE, AND POWER COLLECTION CENTER (PCC)After completing the array structure installation, the J-boxes weremounted at the inner ends of the rows to collect the power from the PVarray. Power cables were laid in the open cable trench and run fromthe J-boxes to the PCC (Figure 4.2-1). Cables between the pole J-boxeswere pulled through the PVC conduit and connected to the respectiveterminal blocks within the J-Boxes. All connections were marked andchecked for continuity. After the checkout, the ground counterpoisecables were laid over the power cables (separated by about six inchesof earth) and secured to the PCC, the fence, and the arrays. Thetrench was filled and later the entire array field was covered withgravel.
4.3 MODULE MATCHINGDuring factory acceptance testing all modules were sorted in one-
quarter ampere module groupings. This grouping allowed for selectingmodules of closely matched performance to be installed in a given 40module circuit. The module manufacturer provided a list of the modulesidentified by grade (See Paragraph 3.2). Hughes prepared a map (Figure4.3-1) of the array, showing the location of each module grade. Eachshipping container label showed the quantity and current grade of themodules packaged inside. Also, each module was conspicuously gradelabeled; therefore, the additional time to install a matched modulearray was insignificant.
4.4 PANEL AND J-BOX INSTALLATIONThe solar panel components (PV modules, panel frames, and fasteners)
were shipped spearately for onsite assembly by the general contractor.This assembly was done on a sheet of 3/4 inch plywood laid across awork stand. The assembly process took place as follows: Four 2 ft x 4ft modles were placed face down on the plywood surface with their edges
and corners aligned with the edges and corners of the plywood sheet;the module support channels were placed along the module ends withtheir holes aligned with the mounting holes in the modules. Stainlesssteel fasteners were inserted and tightened to complete the panel
assembly. Figure 4.4-1 depicts this operation.
16
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While on the work table, the panel support legs were loosely bolted tothe panel. this assembly was then carried by two technicians to itsassigned location on an array row (Figure 4.4-2) where the lower panelchannel extensions were placed on the ground just behind the frontfoundation stanchions. The rear of the panel was then raised to allowthe lower end of the panel support legs to be bolted to the rearfoundation stanchions (Figure 4.4-3). The front of the panel rails was
then lifted and bolted to the front stanchions. A team of twoinstallers was used to accomplish these panel .installation steps.
A J-box mounting channel (Figure 4.3-1) was mounted onto each of theinner row end panel structures in the orientation and locationspecified in the figure. The panel structure was match drilled to the
holes in the mounting channel. The channels were then bolted to thepanel structure, and the J-boxes were bolted to the mounting channel,completing the J-box installation.
4.5 ARRAY WIRINGThe PV array wiring turned out to be a very quick and simple operation,
a few seconds per connection, by using the Solarlok connectors andjumper cables (See Figure 4.5-1). PV modules were daisy-chain wired byrelatively unskilled personnel. The wiring from the arrays to the Jboxes were deferred intentionally as a safety measure until allpreliminary testing and checkout were completed. Final hook-up wasperformed as the system was readied for commissioning tests.
5.0 CHECKOUT, TEST, AND EVALUATION
5.1 PHOTOVOLTAICS (PV)After all the modules had been installed, both the front and backsurfaces of each module were inspected for gross damage. As mentioned
in Section 3.2, two modules had been found to have slight shippingdamage (later repaired) that did not affect their performance.
The PV modules in a 40 module string were series, daisy-chain connectedusing the Solarlok jumper cables. The string of modules was thenconnected to the J-boxes.
An I-V curve of each 40 module string was obtained. Simultaneously,module temperature and solar intensity (at the modulels orientation of
35 0 to the horizontal) were recorded. Temperature was recorded bytaping a thermocouple to the back surface of a module, a technique that
results in a conservative estimate of power when corrected to 25 0 C;the measured temperature of the back surface of the module is somewhatcooler than the actual solar cell junctions.
Intensity was obtained from an Epply pyranometer placed adjacent to andat the same angle as the string of modules being measured. The I-Vcurve was generated on an automatic sweep load provided by Sandia.This equipment also determined and printed out short circuit current
(I sc )' open circuit voltage (Voc )' current at the maximum power point(Imp)' and voltage at the maximum power point (Vmp )'
Current readings were corrected to standard intensity with thefollowing formulae:
Where:
Isc = Recorded short circuit current
lIse = Short circuit current @1000 W/m2
Imp = Recorded maximum power current
limp = Maximum power current @ 1000 W/m2
26
~Isc = Difference between short circuit current @1000 W/m2
and recorded short circuit currentE = Recorded pyranometer intensityEI = Pyranometer intensity @1000 W/m2
Voltage readings were corrected for temperature with the followingformulae:
~V = 1.1424 v/oe (T-250e)V1
mp = Vmp + ~V
VI
OC = Voc + ~V
Where:
T = Recorded temperature~V = Voltage difference due to temperature difference between
recorded temperatures and 250eVmp = Recorded maximum power voltage
Vl
mp = Maximum power voltage at 250eVoc = Recorded open circuit voltage
VI
OC = Open circuit voltage at 250e
Each pole (both upper and lower strings connected in parallel) was alsotested in a similar manner.
Table 5.1-1 shows both the raw and corrected data. The three lettercode indicates from which string the data was obtained.
1st Letter: W= WestE = East
2nd Letter: A = 1st RowB = 2nd Rowe = 3rd Row
3rd Letter: U = Upper stringL = Lower string
P = Upper and lower strings in parallel
27
PVAR
RAY
ELEC
TRIC
AL
PERF
ORM
AN
CE
TABL
E5
.1-1
STR
ING
HAU
WAU
WAL
WAL
WAL
EAU
EAU
EAL
EAL
EBU
TIM
E(M
ST)
11
:15
11
:21
11
:24
11
:26
11
:30
11
:37
11
:39
11
:43
11
:46
12
:00
Ise
(AM
PS
)
12
.7
13
.5
13
.3
13
.3
13
.4
13
.5
13
.8
13
.4
13
.9
13
.3
Voe
(VO
LTS)
257
260
258
258
258
260
261
258
258
258
Imp
(AM
PS
)
11
.1
11
.7
11
.6
11
.6
11
.6
11
.7
12
.3
11
.9
12
.2
11
.7
Vmp
Pmp
(VO
LTS)
(WA
TTS)
203
2267
204
2414
202
2350
203
2364
203
2364
207
2442
203
2509
198
2368
198
2439
201
2372
INSO
LATI
ON
(MV
x10
0)
930
928
946
958
951
947
982
956
984
912
T (OF
)
89 88 87 86 88 83 83 84 85 90
INTE
NSI
TYCO
RREC
TIO
N
1.0
69
9
1.0
72
2
1.0
51
8
1.0
38
6
1.0
46
3
1.0
50
7
1.0
13
3
1.0
40
8
1.0
11
2
1.0
91
0
6Is
e(A
MP
S)
.88
8
.975
.69
9
.51
4
.62
0
.68
4
.18
3
.54
7
.15
5
1.2
1
,Im
p(A
MP
S)
11
.99
12
.67
12
.40
12
.11
12
.22
12
.38
12
.48
12
.45
12
.35
12
.91
b"V
t(V
OLT
S)
7.6
1
6.9
7
6.3
4
5.7
1
6.9
7
3.8
0
3.8
0
4.4
4
5.0
7
8.2
4
,Vm
p(V
OLT
S)
21
0.6
21
1.0
21
0.3
20
8.7
21
0.0
21
0.8
20
6.8
20
2.4
20
3.1
20
9.2
,Pm
p(W
ATT
S)
2525
2674
2608
2528
2566
2611
2581
2520
2509
2701
f\)
CDEB
U
EBL
EBL
WBU
,·lE
U
HBL HBL
WCU
HCU
HCL
WCL
12
:03
12
:06
12
:09
12
:16
12
:18
12
:21
12
:23
12:3
2
12
:35
12
:37
12
:40
13
.7
13
.0
13
.6
14
.1
14
.0
13
.8
13
.7
14
.3
14
.2
13
.8
13
.8
260
256
256
258
258
255
255
257
256
253
253
12
.1
11
.1
11
.7
12
.4
12
.4
11
.8
11
.9
12
.7
12
.5
12
.1
12
.0
203
203
202
202
202
201
200
202
202
195
196
2472
2279
2386
2530
2518
2384
2382
2578
2542
2372
2375
920
939
977
983
975
977
975
973
960
966
968
90 89 90 92 90 95 95 94 96 96 95
1.0
81
5
1.0
59
6
1.0
18
4
1.0
12
2
1.0
20
5
1.0
18
4
1.0
20
5
1.0
22
6
1.0
36
5
1.0
30
0
1.0
27
9
1.1
2
.775
.25
1
.172
.28
7
.254
.281
.32
3
.51
8
.414
.385
13
.22
11
.88
11
.95
12
.57
12
.69
12
.05
12
.18
13
.02
13
.02
12
.51
12
.38
8.2
4
7.6
1
8.2
4
9.5
1
8.2
5
11
.41
11
.41
10
.78
12
.05
12
.05
11
.41
21
1.2
21
0.6
21
0.2
21
1.5
21
0.2
21
2.4
21
1.4
21
2.8
21
4.0
20
7.0
20
7.4
2792
2501
2513
2659
2667
2560
2575
27
71
2786
2591
2569
PVAR
RAY
ELEC
TRIC
AL
PERF
ORM
ANCE
(CO
NT.
)
TABL
E5
.1-1
STR
ING
ECU
ECU
ECL
ECL
ECP
ECP
:rIM
E(M
ST)
12
:45
12
:48
12
:50
12
:54
1:0
0
1:0
3
Isc
(AM
PS)
14
.1
14
.2
13
.8
13
.7
27
.4
27
.7
Voc
Imp
(VO
LTS)
(AM
PS)
255
12
.5
255
12
.4
253
11
.9
254
11
.9
256
23
.8
256
24
.3
Vmp
Pmp
(VO
LTS)
(WA
TTS)
198
2498
201
2503
198
2368
198
2368
202
4839
201
4903
INSO
LATI
ON
(MV
x10
0)
968
980
963
963
942
970
T (OF
)
96 93 94 91 90 88
INTE
NSI
TYCO
RREC
TIO
N
1.0
27
9
1.01
53
1.0
332
1.0
332
1.05
63
1.02
58
6Is
c(A
MPS
)
.393
.217
.459
.455
1.5
42
.71
4
•Im
p(A
MPS
)
12
.89
1262
12
.36
12
.36
25.3
4
25
.01
6V
t(V
OLT
S)
12
.05
10
.14
10
.78
8.8
8
8.2
4
6.9
7
•Vm
p(V
OLT
S)
21
0.0
21
1.1
208.
8
20
6.9
210.
2
20
8.0
,Pm
p(W
ATT
S)
2708
2664
2580
2556
5328
5202
256
24
.319
748
22W
CPf\
)
\.0
IW
CP
WBP
WBP
EBP
EBP
EAP
EAP
WAP
WAP
*W
AP*
1:1
1
1:1
4
1:2
6
1:2
9
1:4
0
1:4
3
1:5
2
1:5
5
2:0
1
2:2
5
2:2
6
27
.2
27
.0
26
.5
25
.5
26
.0
25
.5
24
.1
23
.4
23
.4
23
.0
22
.4
256
256
256
255
254
254
255
257
258
257
24
.1
22
.9
21
.9
22
.4
22
.2
21
.2
20
.5
20
.6
20
.3
19
.8
198
203
203
202
200
197
198
198
196
194
4803
4669
4472
4544
4443
4199
4079
4103
4007
3864
942
933
920
900
913
894
844
820
816
834
778
92 91 89 94 88 89 87 87 84 82 82
1.05
63
1.06
65
1.08
15
1.1
05
6
1.08
98
1.1
13
0
1.17
89
1.21
34
1.2
19
4
1.1
93
1
1.27
89
1.5
31
1.7
94
2.1
6
2.6
9
2.3
4
2.8
8
4.:n
4.9
9
5.1
3
4.4
4
6.2
5
25
.83
25.8
9
25
.06
24
.59
24
.74
25.0
8
25
.51
25
.49
25
.73
24.7
4
26.0
5
9.5
1
8.8
8
7.6
1
10
.78
6.9
7
7.6
1
6.3
4
6.3
4
4.4
4
3.1
7
3.1
7
206.
5
20
6.9
21
0.6
213.
8
20
9.0
20
7.6
20
3.3
20
4.3
202.
4
19
9.2
19
7.2
5334
5357
5278
5257
5169
5207
SIR
S
5209
5209
4927
5136
*LA
MP
POST
SHAD
OWED
MOD
ULE
All strings and poles performed satisfactorily.
Several modules in the A row were fully or partially shadowed todemonstrate that the module shunt diode design worked effectively. Theperformance of the shadowed strings was as predicted. The diodes ofthe shadowed modules "turned on," and the string voltage was reduced bythe amount of the diode drop and the loss of the shadowed module'svoltage output.
5.2 J-BOXES AND CABLING
Continuity tests were made on the cabling during the installation ofthe cables. The array was connected in stages to the J-boxes andvoltages were measured at the terminal blocks. Voltage was not placedon the cables as they were not wired into the PCMs.
5.3 POWER COLLECTION CENTER (PCC)No formal test procedure was prepared because of the checkout'ssimplicity. The system schematic was used and methodical checkoutswere conducted. The PCMs had been checked during factory assembly.The two PCMs were mounted into the PCC and the cable connections made.
Voltage measurements were made at the input and output of the PCMs.The disconnect switches were operated, and the voltage was checked atthe main lugs. The manual crowbar on the PCMs was operated, andvoltage and current measurements made. The ground faultindicator/detector was installed and checked out.
A temporary test panel was installed in the rear of the PCC so thatmeasurements could be made in the field. The test panel wa~ used torun I-V curves during the test phase. As part of the testing, theSandia load bank was used for the initial load test. The overalltesting went very well and the system performed better than expected.
30
6.0 ECONOMIC ANALYSISFabricating, installing, and testing the 30 kW Modular PhotovoltaicArray Field (MPAF) were undertaken primarily to verify the costprojections developed during the Array Field Optimzation and Modularity(AFOM) Study. Detailed records on material, labor, installation, andtest costs were maintained. A listing of the MPAF material andsubcontract procurements is shown in Table 6.0-1. These costs aresubsequently summarized in terms of dollars per square meter of BOScosts. The 30 kW array field consists of 356 square meters ofphotovoltaic collectors.
In the original AFOM Study, a life cycle cost analysis was performed.In it the following economic factors were assumed:
Dedicated factory producingSystem operating lifetimeEffective income tax rateGeneral inflation rateEscalation rate for capital costEscalation rate of 0 &McostBase year in constant dollarsCost of capital
10 MEGAWATTS/YEAR20 YEARS
40%12%12%12%
198015%
The following burdened labor rates. including a nominal profit of 10percent, were also used:
Factory Labor
Field LaborSemi-skilledSkilledSupervisory
Material Cost Make-upShipped directly to siteProcessed at factory
31
$18.50/Hr.
$20.00/Hr.28.00/Hr.35.00/Hr.
+20%+30%
MATERIAL AND SUBCONTRACT PROCUREMENTTABLE 6.0-1
DESCRIPTION VENDOR PRICE
PV MODULES SOLAREX CORP. $316,211ROCKVILLE, MD
GE MOVS HAMILTON CO. 75LOS ANGELES, CA
BLOCKING DIODES KIERULFF 164LOS ANGELES, CA
J-BOX CORE PICO 370LOS ANGELES, CA
ARRAY WIRING &CONNECTORS AMP 2,153LARGO, FL
MISC. ELECTRICAL HARDWARE VARIOUS 334
PVC ADAPTERS/COUPLINGS/ GRAYBAR 229ELBOWS LOS ANGELES, CA
100 kW ENCLOSURE CEO 3,485LOS ANGELES, CA
CABLES GE SUPPLY 914LOS ANGELES, CA
STRUCTURES &FOUNDATIONS A &M 6,519LOS ANGELES, CA
1/4 GALVANIZED WIRE VER SALES INC 135LOS ANGELES, CA
GENERAL CONTRACTOR ABBOTT 32,897ALBUQUERQUE, NM
CIRCUIT BREAKERS CROWBAR GRAYBAR 215LOS ANGELES, CA
STRUCTURES HARDWARE LAVENDER 1,127COSTA MESA, CA
TOTAL $364,828
32
Based on these factors, the AFOM BOS costs (at price to the customer)projected for a 100 kW modularized system are shown below along with
(a) the actual BOS costs experienced in the MPAF 30 kW project; and(b) the projected BOS costs for a second MPAF system, 100 kW, if
it were to be built in 1983 based upon the fabrication andinstallation experience gained from the 30 kW MPAF.
(a) Electrical Hardware: Acquisitions costs of parts, subassemblies,factory test, and transportation to site.
(b) Structures/Foundations Hardware: Acquisition costs of parts,subassemblies, attachment hardware, and transportation to site.
(c) Field Installation: Costs for site preparation, trenching,concrete, field assembly, installation and checkout of theelectrical and mechanical subsystems, and ground sterilization.
A factor of two exists between the AFOM projected costs and the 30 kWMPAF actual costs. Most of this difference stems from the 30 kW arrayhaving been a "one of a kind project" and not part of an overall 10 MWannual production base. Also, as this 30 kW array was the firstmanufactured article of the AFOM design, much greater attention was
paid to the PV modules, power conditioning, and structural subsystemsthan would have occurred if this were one of many factory fabricated,installed projects.
33
As the MPAF was only a 30 kW array consisting of several small volumeprocurements~ no price breaks could be obtained on material purchases,such as PV modules, PV jumper cables~ connectors~ field cables~ orstructural elements.
Also~ this project was essentially an "engineering" project rather thana "production/factory" project; therefore~ expensive engineeringpersonnel performed tasks~ such as quality assurance and control~ siteinstallation supervision, vendor liaison~ and electrical test andcheckout, that normally would have been delegated to lower paid semiskilled personnel. Costs for the indirect labor that participated inperforming these MPAF tasks were not included in the summary costsshown above to present a more accurate comparison.
Notwithstanding the above and taking into consideration the recommendations discussed in Section 7.0 following, Hughes undertook a costingexercise to project the costs of a second MPAF of essentially the samedesign, but increased from three to ten building blocks (100 kW). Theestimated system BOS costs are shown in column three of the above costsummary table~ assuming fabrication and installation in 1983. Thesecosts were derived from vendor quotations and engineering costestimates. For example~ having now gained the experience of thefirst field installation of the 30 kW MPAF, the services of a generalcontractor would be eliminated in favor of direct subcontracting forthe field skills needed. More than 30 percent savings will be realizedfor this BOS element alone. The support structure front feet would beconnected using concrete foundations and stanchions. The PCC enclosurewould be more cost effective as its costs would be amortized over theten building blocks instead of three.achieved by factory assembly of the PVpanels.
Additional cost savings aremodules and support legs into
7.0 RECOMMENDATIONSProcuring and installing an actual modular photovoltaic array fieldbased on the AFOM study provided an opportunity to recognize improvements based on "hands-on " experience. Future array fields using the
34
AFOM study as a design base should incorporate the recommendationsdiscussed in the following paragraphs.
7.1 ELECTRICAL HARDWAREThe PV modules used in the MPAF system were essentially a custom solar
cell module design as defined by Hughes (Appendix A). Significantsavings would be realized through eliminating costs for special
production tooling, reductions in engineering liaison, and qualitycontrol surveillance by selecting a standard "off-the-shelf,"
qualified, commercial module (Ref. 2).
Fabricating and assembling certain parts in the factory rather than inthe field is more cost effective. For example, significant savings can
be realized by the factory assembly of modules and support legs intopanels. Additional savings would be incurred by reducing thelogistical problems attendant with the necessity for modules, frames,hardware, and personnel arriving at the array site in a timely manner.
Similarly, the Power Control Module (PCM) and the Power CollectionCenter (PCC) could also be fabricated, assembled, and tested by thesame vendor in his factory and shipped as a unit to the installation
site. This process would also reduce costs associated with high pricedelectricians performing electrical assembly tasks in the field and
would further reduce the risk of equipment damage due to assemblyerrors during field installation.
Because the MPAF system was essentially a prototype, much of the
electrical test equipment was borrowed and/or field adapted to performthe electrical checkout and commissioning verification tests. These
tests would be performed more efficiently using test equipmentspecifically designed for this modular array field.
35
7.2 FOUNDATIONSDuring the AFOM design study and analysis, the buried metal front footdesign, acting as both the foundation structural member and theelectrical earth ground for the array, was found to be the most costeffective. From the experience gained during this 30 kW MPAFinstallation, and, notwithstanding the cost of adding an earthelectrode grounding counterpoise, a foundation utilizing a concretecurb for both the front and the rear PV panel foundation was found tobe more cost effective. Smoothing trench bottoms to accept the earthfoot front foundations and the alignment of these foundations consumedmore installation time than planned. The installation would proceedmore quickly if both front and rear stanchions were bolted onto thealignment angles, placed into trenches, tapped into a level position,and the trenches filled with concrete.
The PV panel wind loads are concentrated primarily on the rearfoundations; therefore, less ballast is required for the front panelfoundation than for the rear panel foundation. The cost of the frontpanel concrete ballast is about the same as the cost of the metal earthfoot. Including the additional cost of PV panel groundingcounterpoise, the installation time saved will still result in anoverall less costly foundation.
7.3 FIELD INSTALLATIONAs discussed in Section 6.0, several semi-skilled tasks were performedby engineering personnel. Labor skills should be matched to theassigned tasks to reduce costs for quality control, installation,checkout and test labor.
Additional installation savings could be realized by eliminating thegeneral contractor and sUbcontracting directly for field constructionand electrical work. Also, consideration of seasonal factors whenselecting construction dates would minimize both lost time and expensesdue to inclement weather.
36
8.0 CONCLUSIONSUnder the PRDA programs sponsored by the DOE/Sandia NationalLaboratories, Balance of Systems (BOS) prices for installed fixed flatpanel photovoltaic systems prices were in the range of $400 to $500 persquare meter (1980$). The BOS cost for the installed ModularPhotovoltaic Array Field (MPAF) 30 kW array field at $118 per squaremeter (1980$) shows marked improvements over those of the PRDAexperience. This installed MPAF cost also compares favorably to theprojected costs developed under the Array Field Optimization and
Modularity (AFOM) design study when the differences in implementing thetwo are reduced to a common base, e.g., one of a kind versus adedicated factory, 30 kW versus 10 mW annual production, etc.
Further cost reductions from procurements of future intermediate size(20 to 500 kW) MPAF systems can be realized if the recommendationslisted earlier are implemented. For example, a preliminary costanalysis for the procurement and installation of a 100 kW MPAF showed a25 percent improvement in BOS costs as compared to the 30 kW MPAFinstallation.
In summary, the MPAF program verified that BOS costs developed underthe AFOM study were achieveable and that future reductions in BOS costscan be realized.
37
9.0 REFERENCES1. "Photovoltaic Array Field Optimization and Modularity Study,"
SAND81-7193, October 1982. Worked performed by Hughes AircraftCompany, under Sandia National Laboratories Contract #62-9188.
2. "Block V Solar Cell Module Design and Test Specification forIntermediate Load Applications - 1982," 5101-161, Jet Propulsion
This specification defines the requirements for the design andconstruction of photovoltaic solar cell modules (herein referredto as the module) to be used for terrestrial applications.
Design Requirements
The module shall be designed to meet all requirements specifiedherein. Designated tests shall be successfully completed demonstrating
the ability of the module to meet all performance requirements of
this specification.
Deviations and Changes
Deviations from or changes to this specification shall not beallowed without written authorization from Hughes.
Applicable Documents
Government documents
The following documents s of the exact issue shown or of the current
issue when no date is shown s form a part of this specification tothe extent specified herein. In the event of conflict between the
documents referenced herein and the contents of this specifications
the detail contents of this specification shall be considered as
binding.
JPl #5l0l-l61 s Block V Solar Cell Module Design and Test
Specification for Intermediate load Applications - (February 20 s 1981)
A4
3.0 Reguirements
3.1 Functional Description
The module specified herein shall be used to convert solar energyto electrical energy in terrestrial applications.
3.2 Performance
The photovoltaic module shall provide the required minimum power
output when subjected to the specified test conditions.
3.2.1 Power Output
The minimum lot average current of the modules shall be 12.69 Amps
(66.0 watts) at 5.2 volts minimum when subjected to the test conditionsdefined in paragraph 3.2.2 No module shall produce less than 11.92
Amps (62.0 watts) at these conditions.
3.2.2 Test Conditions
Solar intensityCell temperature
1000 W/m2, AM 1.5
25° C minimum
3.3 Design
3.3.1 Electrical Design
All module circuitry, including output terminations shall be insulated
from the electrically conductive external surfaces. Leakage current
A5
3.3.1.2
3.3.1.3
3.3.1.4
3.3.2
3.3.2.1
shall not exceed 50 microamps when a potential of 3000 VDC is
applied between the external conductive surface and the output
terminals.
Electrical Interface
E~rh tprmin~l on the module shall be equipped with an AMP
SOLARLOK connector bus bar housing No. 121044-1. The polarity of
each socket shall be clearly marked in a permanent and legible
manner. Positive and negative terminals shall be located at
opposite ends of the module.
Bypass Diode
Each module shall have an integrated bypass diode electrically
connected across the output terminals. The forward direct current
capacity of the diode shall be greater than 1.1 times the module
short circuit current and derated for a temperature of 75° C. Thepeak inverse voltage rating of the diode shall be not less than
250 volts.
Reliability and Redundancy
The module shall meet or exceed the reliability and redundancy
requirements of Section II, Part B, Paragraph 4 of the referenced JPL
Specification 5101-161.
Mechanical Design
Moisture Protection
The module encapsulation matrix may be protected from moistureincursion with an impermeable barrier of metal foil having a minimum
thickness of .0015 inches.
A6
3.3.2.2
3.3.2.3
Geometry
Overall dimensions and hole locations shall conform to Figure 1.
Optical Surface
The illuminated optical surface of the module shall be temperedlow iron glass 0.188 inch thick minimum and shall conform to therequirements of Section II, Part C, paragraph 3 of the referencedJPL specification 5101-161.
3.3.2.4 InterchangeabilityAll modules shall be physically interchangeable.
3.3.2.5 Defects
3.3.2.5.1 Rejections
Modules with the following defects shall not be accepted:
a) Cracked or broken front surfaceb) Cracked or broken framec) Cracked or broken solar cells which:
1) Isolate a portion of a cell from either apositive or negative interconnect. Cornercracks having a hypotenuse less than 0.5 inchshall not be a cause for rejection.
2) Terminate or pass through or under an interconnectsolder joint.
3) Are caused by point impact.d) Cracked or broken interconnectse) Cells with unsoldered solder jointsf) Laminate voids greater than 1/4 inch diameter and
1 square inch total area per moduleg) Loose or broken terminalsh) Broken diodes or diode connections
3.3.2.5.2 Allowable Cosmetic Defects
At the discretion of Hughes, selected cosmetic defects which do notaffect form, fit, function or reliability may be permitted.
A7
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3.6
4.0
4.1
Operational Life
The module shall be designed for an operational life of at1east 20 years.
Environment
As a minimum the module design shall be capable of withstandingexposure to the environmental tests defined in Section V of referenceJPL Specification 5101-161. The module shall also be capable ofmeeting the requirements of the Hot Spot Endurance Test of Section II,Part 8, paragraph 5 of the JPL Specification 5101-161.
Identification
Each module shall be legibly identified with the following:
a) Se11~r part numberb) Serial numberc) Current at test voltage
Quality Assurance Provisions
General
The product covered by this specification shall be subject toinspection and testing by both the seller and Hughes in accordancewith the quality assurance provisions of this section.
4.1.1 Interface Control Drawing (ICD)
Prior to the manufacturing of modules for this Hughes program,the vendor shall generate an IIInterface Control Drawing ll (lCD).This drawing shall identify the configuration, dimensions, partsand materials used in module fabrication. This ICD shall be submittedto HUQhes for approval prior to module fabrication. Any changes
thereafter affecting the performance or integrity of the module orthe ICD shall be submitted for approval to Hughes prior to intendedimple~entation of such changes.
A9
4.2 Reguirement Verification
4.2.1 Test and/or Inspection
Requirements specified in Section 3 of this specification and
listed in 4.2.3 (Requirements/Specification Matrix) shall be
verified by the applicable paragraphs of Section 4.
4.2.2 Certification
Requirements specified in Section 3 of this specification not
verified by inspection or test shall be satisfied by a submittalto Hughes of documentation showing evidence of conformance in the
Broken Diodes or Diode ConnectionsOperational Life
Environment
Identification
AlO
4.4.2
4.4.3
4.4.1
4.2.2
4.2.24.2.2
4.4.14.2.2
4.2.2
4.4.1
4.4.1/4.4.4
4.2.2
4.54.4.1
4.3
4.3.1
4.3.2
4.3.3
4.3.4
4.3.4.1
Inspection and Test Methods
Hughes Source Inspection
The Hughes Aircraft Companys mays at its options provideinspection to monitor the seller's quality control procedures.The completed hardware may be source inspected by Hughes to assurethat the product conforms to all the requirements specified on
the applicable drawings and specifications.
Test location
Unless otherwise specified in the contract, qualification andacceptance tests shall be performed by the seller at the seller'splant. If the use of outside test facilities is required, suchuse shall be subject to approval by Hughes. Hughes shall have theright to witness, inspect and review all qualification and acceptance
tests.
Test Conditions
Unless otherwise specified herein, all tests shall be performed
at a temperature of 25 + 5°C.
Test Equipment
Test Equipment Accuracy
All meters, scales, thermometers and similar measuring equipmentused in conducting tests specified herein shall be accurate withinone percent of full-scale value except temperature which shall be
accurate within ~ 1°C. Full-scale deflection of meters shall notbe more than twice the maximum value of the item being measured.
All
4.3.4.2
4.3.4.3
Test Equipment Calibration
All test apparatus shall be calibrated at proper intervals and
records of such calibration shall be available for Hughes inspection.Hughes may examine the seller's test equipment and determine that
they are of the proper type and range to make measurements of the
required accuracy and are in calibration.
Solar Simulator
The solar simulator shall be capable of simulating air mass 1.5spectral conditions and a solar radiation intensity of 1000 W/m2•
The solar simulator intensity shall be calibrated and verified using
a Hughes approved standard solar cell which is traceable to a JPLcalibrated standard. The simulator may be either a constant xenon
light source or pulsed xenon type.
4.4 Acceptance Tests
4.4.1 Examination
Each module shall be visually inspected for compliance to the
following paragraphs: 3.3.1.2, 3.3.2.2, 3.3.2.5, 3.6, and theICD (4.1.1).
4.4.2 Electrical Performance
The seller shall test each module under the test conditions
specified in paragraph 3.2.2 to verify the output requirement of
paragraph 3.2.1. The solar simulator used for this test mustcomply with paragraph 4.3.4.3.
A12
4.4.3
4.4.4
4.4.5
A full current-voltage (I-V) characteristic curve is required
for each module. If a pulsed xenon type simulator is utilized,a minimum of 5 data points along the I-V curve is required including
short circuit current, current at rated voltage and open circuit
voltage.
Electrical Voltage Insulation Test
Each module shall be subjected to a "Hi-Pot" test conducted withthe output terminations shortcircuited. The leads from a suitabledc voltage power supply shall be connected with the positive lead
on the terminals and the negative lead on the module frame. Voltage
shall be applied at a rate not to exceed 500 V/sec up to the test
voltage of 3000 Vdc, and then held at this test voltage for at least
1 minute. The module shall be observed during the test and there
shall be no signs of arcing or flashover. Leakage current shall
be monitored during the test and shall not exceed 50 microamps.
Diode Verification Test
A diode verification test shall be performed on each module to insure
that none of the bypass diodes or their associated connections
have open or short circuits. The procedure for this test shall be
submitted to Hughes by the Seller for approval prior to performance
of this test.
Hughes Electrical Performance Tests
Upon preparation for shipment of each lot of modules Hughes willrandomly select one module for each 50 modules in the lot. These
selected modules will be retested by Hughes in accordance withparagraph 4.4.2. If the Hughes average values of power at the test
voltage for the sampled modules vary from the vendors values by
more than 2%, acceptance of the shipping lot shall be withheld pendingfurther testing and investigation.
Al3
4.5 Qualification Tests
The module defined by the lCD shall be subjected to QualificationTesting specified below.
4.5.1 Initial Tests
All modules selected for qualification testing under paragraphs4.5.2 and 4.5.3 shall be first subjected to and successfully pass
acceptance testing as defined in paragraph 4.4.
4.5.2
4.5.3
4.5.4
Environmental Tests
A minimum of four modules shall be subjected to the environmental
tests defined below in accordance with Section V of referenceJPL specification 5101-161. Module electrical performance measurements
(4.4.1) and visual inspection (4.4.2) shall be conducted after eachexposure. The tests shall be conducted in the order indicated:
The Environmental Tests' Pass-Fail criteria are defined by
Section III, Part B, Paragraph 7 of referenced JPL Specification 5101-161.
Hot-Spot Endurance Test
One module shall be subjected to a Hot-Spot endurance test for a cumulative
exposure period of 100 hours. The test shall be conducted using theprocedures described in Appendix C of the JPL Specification 5101-161.
Simultaneously with this hot spot endurance test the thermal configurationof the bypass diode assembly shall also be endurance tested. A separate
power supply shall be connected to the diode with polarity arranged to
drive a current equal to the module short circuit current through thediode. The test execution and inspection shall be the same as that
described in paragraphs(3C), (4), (5) and (6) of Appendix C of JPL
Specification 5101-161. The temperature of the diode shall be monitored
rluring the course of the hot spot endurance test. The sample shall satis~
A14
4.6
4.6.1
4.6.2
4.6.3
4.7
the criteria for qualification stated in Section III, Part B,paragraph 7 of the reference JPLSpecification 5101-161 at theconclusion of the test. The sample subjected to the Hot-Spotendurance test shall not be subjected to the environmental testsequence of paragraph 4.5.2.
Rejection and Retest - Production Modules
Rejected Modules
Modules rejected by Hughes shall not be resubmitted for acceptance without
furnishing full details concerning the rejection, the measure takento overcome the defects, and the prevention of their future occurence.Each rejected module shall be identified by a serialized rejection
tag. This rejection tag shall not be removed until rework requirementshave been complied with.
Defective Modules
Notwithstanding the warranty of individual modules, if, afterreceipt by Hughes, a large number of modules prove defective,such as to indicate a vendor manufacturing problem, the entire
lot may be rejected.Retest
Any unilateral changes from Paragraph 4.1.1 by the supplier inmanufacturing techniques, processes, materials, quality control levels,or type of manufacturing equipment shall be cause for complete
retest per paragraph 4.5 at no cost to Hughes.
Test Records
Records shall be kept of all tests and of applicable manufacturingdata, and these records shall be made available to Hughes. All
physical markings, defects and other visual characteristics shall
A15
be noted and recorded as a portion of the test record.
One copy of each module's I-V curve shall be included in theshipping container with the module. An additional copy of theI-V curve shall be sent to Hughes' Solar Energy Projects Office.
5.0 Preparation for Delivery
5.1 Packaging
The Seller shall package the modules into shipping containers whichadequately protect the modules from shipping d~mage. The shippingcontainers shall be palletized.
5.1.2 Module Current Grouping
Each module when tested at 5.2 volts per paragraph 4.4.2 shall be sortedinto current groups as shown below:
Current GroupABCDEFGHIJKL
5.2 Marking
5.2.1 Modu1 e
Current Output atFrom11 .27 AMPS11.5011.7512.0012.2512.5012.7513.0013.2513.5013.75Greater than
Each module shall be legibly identified with the following:
a) Module current and voltage measurement value.b) Current group.c) Seller's part number (if applicable) and serial number.d) Lot number if applicable.
e) Month and year of manufacture.
A16
5.2.2 Shipping Container
Each shipping container shall be ligibly identified withthe following:
a} Hughps part number {specification number}.b} Serialized container number.c} Quantity of modules in each current group
residing in the container.
6.0 Warranty
The contractor shall warrant that the solar cell modules offeredwill be free from defects in material, workmanship, and performancefor a period of not less than three {3} years after acceptance byHughes Aircraft Company. During the warranty period all modulesfound to have defects not caused by misuse or accident throughfault or negligence by Hughes or end user must be replaced atSeller's expense.
A17-18
APPENDIX B
GENERAL CONTRACTORSTATEMENT OF WORK
Bl-2
CONTRACTOR'S STATEMENT OF WORK
FOR
INSTALLING 30 KW PHOTOVOLTAIC ARRAY FIELDS
AT
SANDIA NATIONAL LABORATORIES, ALBUQUERQUE, NEW MEXICO
1) The site is located on the facilities of Sandia National Laboratories.Clear and flatten array field area. (Reference: Sandia location plan).
2) Perform site survey, location and staking of all trenches for areafoundation, power cabling, grounding counterpoise and Power Control Centerpad. (Reference: Hughes Drawings SEP 11340 and 11341).
3) Perform all trenching (Reference: Hughes Drawings SEP 11340 and 11341).
4) Install the photovoltaic panel structure foundation trench feet (Reference:
Hughes Drawing SEP 11330). This involves light raking so the trench bottom is
relatively flat and free of debris. Place the support structure feet onto
the trench bottom, bolting the stanchions to the feet and attaching thealignment bars to the stanchion tops. Check upright and level position andsecure. Backfill foot trenches except leave the trench ends clear for Step 9.
to allow for attaching the grounding counterpoise to the lower ends of thestanchion rows.
5) Install rear, concrete curb stanchions. This involves: Bolting long alignmentbars to installed and secured front stanchions. Place rear stanchions in trench
and bolt to long alignment bars. Attach short alignment bars and place theconcrete reinforcing rebar through the lower stanchion holes. Back stanchionswill be at right angles and level with respect to front stanchions and securedfor concrete pouring.
panel assembly must be assembled concurrently with foundation installation, so
that they will be ready for Step 11.
----- -
Preceding page blank
7) Form Power Control Center (PCC) concrete pad above ground (3 1 x 4 1 X 4" deep).
8) Pour concrete into concrete curb trenches and PCC pad form without allowingconcrete into the center cable trench.
9) Remove alignment spacers from support structure stanchion bars.
10) Attach the rear panel support leg to the rear stanchion.
11) Install photovoltaic panels. (4 men can install 1 panel). This involves
carrying the panel to the foundation stanchions, bolting the front PV panel
legs to the front stanchions, raising the panel rear and bolting in the rearPV panel support legs to the PV panel. Tighten all bolts.
12) Install J-Boxes. These units are approximately 8" x 12" X 12" and will beattached to the inner end of each PV panel row (Reference: Hughes DrawingSEP 11361 and 11362). The exposed panel side support channel at each inner
row end will be match drilled to fit the J-box mounting holes. Bolt on the
J-boxes to the side support channel (6 required for each 30 KW field).
13) Install Power Control Center onto the PCC concrete pad.
14) Attach risers to PCC and J-boxes.
15) Lay the field cables into the cable trenches and run through conduit risers
and up to the PCC and J-boxes. Check cable continuity and identifyappropriately.
16) Back-fill cable trenches to one-half depth.
17) Lay in and attach grounding counterpoises from earth-foot stanchion row ends.
18) Lay the central grounding counterpoise into the half filled cable trench and
attach to the grounding counterpoises from the earth foot stanchions and to the
ground point on the PCC.
19) Back-fi 11 groundi ng trenches.
B4
20) Assist Hughes in the interconnection of the PV modules and tie down loosewiring at outer array row ends. This involves simply plugging in factoryassembled jumper cable assemblies into adjacent modules. (Approximately 9
hours per 30 KW Array Field).
21) Assist Hughes in performing system electrical checkout. (Bid 30 hours for
the 30 KW array field).
Hughes will supply the following:
1) PV Modules.2) Foundations and structures per parts list and HAC Drawings
SEP 11330.3) J-Boxes, pre-assembled, ready for mounting and connecting.
4) PV array back panel harnesses.
5) Power cables, grounding cables, lugs and hardware.6) Power collection center (PCC) enclosure.7) PVC pipe (risers) and elbows, etc.
General Contractor will supply the following:
1) Manpower and equipment.
2) Concrete for trenches and PCC pad.3) Hisc. hardware.
Note: (Ref. Drawings SEP 11340 and SEP 11341)
There will be no fence or gate. See Sandia location plan.
B5
2x4 FOOTSOLAR CEUYOOULE
GALVANIZED -/":STEEL / 'CHANNELS ----------!~
METAL FOOTfOUNDATION
SUBARRAY STRUCTUREAND HYBRID FOUNDATION
B6
PVC CABLERISERS FORDIRECT BURIALCABLE
APPENDIX C
BLOCK IV TEST DATA
Cl-2
•11111111111 SOLAREX
October 18, 1982
Mr. George NaffHughes AircraftP.O. Box 9399Building A-I, MIs 4C 843Long Beach, California 90810-0399
Dear Mr. Naff:
During discussions with you we agreed to furnish you data on how ourBlock IV modules passed Block IV testing (Ref: JPL Document 5101-16, Rev. A)in the areas of mechanical loading, twisted mounting surface, and hail impacttests. Below are data which illustrate the characteristics and specificationsof the two modules:
The Solarex Block IV modules passed all these tests both at Solarex andat JPL (only JPL did the hail test). Dates are as follows:
MECHANICAL LOADING
TWISTED MOUNTING
HAIL IMPACT
SOLAREX
May 1980
May 1980
JPL
August 14, 1980
August 20, 1980
August 26, 1980
You will note that the Block IV specification calls for one module to betested to destruction by increasing the velocity of the iceball until theglass breaks, this occurred at 100 mph.
In view of the fact that the module geometry is virtually identical inboth modules, I have no hesitancy in recommending to you that you accept thesetests as sufficient validation. I therefore request that para. 4.5.2 3), 4),and 5) of HAC Spec. 11387 be considered as satisfied.
Sincerely,
SOLAREX CORPORATION
~o----~ ~ ,.J-~-James F. HoelscherProgram Manager
JFH:prf
cc:
Ms. Helen LopezBuilding A-I, M/SlB 708Long Beach, California 90810-0462
c4
APPENDIX D
ENVIRONMENTAL TEST REPORTS
Dl-2
ENVIRONMENTAL TEST REPORT
ON
HUGHES/SANDIA PHOTOVOLTAIC MODULES
DECEMBER 2, 1982
PREPARED BY
COLIN SHELLUM
QUALITY ASSURANCE
---------
Preceding page blank
1.0
2.0
3.0
4.0
5.0
6.0
7.0
TABLE OF CONTENTS
PURPOSE
INTRODUCTION
MODULE CONFIGURATION
INSPECTIONS AND ELECTRICAL TESTS
ENVIRONMENTAL TESTING
ENVIRONMENTAL TEST RESULTS
CONCLUSION
D4
PAGE
1
1
1
2
2
3
4
TABLE 1 -
TABLE 2 -
FIGURE 1 -
FIGURE 2 -
FIGURE 3 -
FI GURES 4-7 -
FI GURES 8- 9 -
TABLES
ELECTRICAL PERFORMANCE SUMMARY
ELECTRICAL VOLTAGE INSULATION TEST SUMMARY
FIGURES
QUALIFICATION TEST FLOW PLAN
THERMAL CYCLE TEST
HUMIDITY-FREEZE TEST
CURVES AFTER 50 THERMAL CYCLES
CURVES AFTER 10 HUMIDITY-FREEZE CYCLES
D5
1.0 PURPOSE
The purpose of this report is to document the performance
of photovoltaic modules manufactured by Solarex in compliance
with Hughes Specification 11387 and purchase order 05-234l68-DTS
"B" •
2.0 INTRODUCTION
Four modules were submitted to Block V environmental
testing as required by Hughes contract specification 11387. In
lieu of doing all tests required by JPL 5101-161, a letter was
submitted to the Hughes program Manager asking for waiver of the
twisted mounting surface test, hail test, and simulated load
cycle test. (See letter of October 18, 1982.) This report
deals only with the thermal cycling and humidity cycling tests.
3.0 MODULE CONFIGURATION
The configuration of the four modules tested (S.N.'s
1,2,3,4) is shown in Drawing D-l0015-03, 2x4 Demonstration
Module Interface Control.
D6
4.0 INSPECTIONS AND ELECTRICAL TESTS
Prior to thermal cycling, all modules were visually
inspected, subjected to hi-pot (3000vdc) tests, and electrical
performance (I-V) tests. These same tests were conducted after
each phase of testing.
5.0 ENVIRONMENTAL TESTING
The four modules selected for testing will be identified by
their serial number when referenced in test results (e.g., 1-4).
The test program consisted of three phases as per Block V
specifications (see Figure 1). In the first phase, all four
panels were subjected to the thermal cycle test of fifty (50)
cycles in which the temperature varied at a rate not exceeding
100oC/hour and with a period not greater than six hours/cycle
(from ambient to -40 oC to +90 oC to ambient). Module circuitry
was instrumented and monitored throughout the phase to monitor
continuity. At the termination of the 50 thermal cycles,
modules '2 and #3 were inspected and returned to the chamber for
an additional 150 cycles (total 200). The last 150 cycles were
run in the same manner as the first 50 (see Figure 2).
D7
Modules #1 and #4 were submitted to 10 humidity-freeze
cycles between -40 oC and +8S oC with 8SRH (t2.S%) maintained at
all temperatures except when impractical. During a cycle,
temperatures of +8SoC were sustained for a minimum of 20 hours
and -40 oC for a minimum of .S hours. The rate of change between
high and low temperatures was 100oC/hour maximum at temperatures
above OOC and 200 oC/hour for those below (see Figure 3). AS in
the first phase the module circuitry was monitored for
continuity.
6.0 ENVIRONMENTAL TEST RESULTS
Prior to testing, all modules were inspected visually and
electrically. Initial visual inspection of modules was
performed by Quality Assurance personnel following guidelines in
Specification 11387. The modules met the requirements of this
specification and normal Solarex inspection procedures for
rejections and allowable cosmetic defects.
Inspection after SO thermal cycles (10-12-82) revealed the
following:
A. Tears in Tedlar substrate of Module 2 due to one
module frame falling against its back (Tedlar) while in
DB
chamber or when removed. Tear #1 is approximately 2 inches long
and is positioned one inch to side of negative AMP connector.
This accident also caused the cell in front of tear to be
cracked/broken. Tear #2 is approximately seven (7) inches to
left and seven (7) inches down from Tear #1. Tear #2 appears as
a zig-zag of about one (1) inch in length.
Inspection after 10 humidity-freeze cycles for modules 1
and 4 (11-4-82) revealed the following:
A. Minor corrosion of diode enclosure assembly of Modules
#1 and #4.
Inspection after 150 thermal cycles (11-30-82) revealed no
significant changes or subsequent degradation in modules 2 and 3.
7.0 CONCLUSION
Electrical degradation was within accepted levels and there
were no signs of corrosion on cells, interconnects and other
module metallization.
Hi-Pot tests recorded allowable leakage current at 3000Vdc
and no arcing or flashover at all stages of testing.
D9
The Hughes modules showed relatively small amounts of
cosmetic degradation after submission to environmental testing.
Their overall final appearance remains excellent.
D10
HUGHES/BLOCK V TEST SUMMARYPARA- AFTER 50 AFTER 10 AFTER 150
SiN METERS BEFORE TESTINC THERMAL CYCLE~ H/F CYCLES THERMAL CYCLE~
ACTUAL ACTUAL % l::. ACTUAL % l::. ACTUAL % l::. ACTUAL % l::.
P T ~LE 1maxVoe HUGHE BMonu E ELECTR CAL P RFORMANC SUMM RYI iaeFF
Dll
AFTER 50 THERMAL CYCLES
10/12/82
AFTER 10 HUMIDITY-FREEZE
10/4/82
AFTER 150 THERMAL CYCLES
12/2/82
MODULE SiN
1
2
3
4
1
4
2
3
TABLE 2
LEAKAGE CURRENT (~A)
@ 3000V de
1.0
0.1
0.4
0.1
.34
2.16
0.0
0.0
ELECTRICAL VOLTAGE INSULATION TEST
D12
ELECTRICAL INSULATION
(HI-POT) TEST
3000V de
1ELECTRICAL PERFORMANCE TEST
AND VISUAL INSPECTION
1
,THERMAL CYCLE (50)
-40 to +90oC(ALL MODULES)
HonULESINSTRUMENTED/
MONITOREDTHROUGHOUT
.~ THERMAL CYCLE (150)ELECTRICAL PERFORMANCE TEST H -40 to +90oC
AND VISUAL INSPECTION (MODULES 2 & 3)'-- ..,.- .-.1
HUMIDITY-FREEZE (10), 8soC/8s\ RH/-40oC
I~
ELECTRICAL PERFORMANCE TEST
AND VISUAL INSPECTION
1FINAL ELECTRICAL
INSULATION (HI-POT)
TEST 3000V de
1EVALUATION OF TEST RESULTS
ENVIRONMENTAL REPORT
FIGURE 1
QUALIFICATION TEST FLOW PLAN
Dl3
1··------ MAXIMUM C'tC11 JlMl --------1
-U....=3z-I', - ICONnNUE FOR I
I, \ SO"S ~5.';~ES "\ II \ . J
II
rieure 2. Thermal Cycle Test (Shorter cycle time i. acceptableif lOOOC/hr maximum rate of temperature change i. Dotexceeded. Chamber may be opened at 2S-cycle 'intervals forvisual inspection.)
PANEL TYPE?HUGHESS/H?••Voe?6.5Isc'?12.4V AT Pmax'?5.21 AT Pllax'?18.75CELLS IN SERIESIPARALlEL?1216CELL AREA IN SQ. C".'?90.25J,JHAT REF USED?G-TOWNCALIBRATED CURRENT AT ONE SUN?1e.4~REF READING DURING TEST'?9.19AMBIENT TEMP IN C'?26STANDARD TEMP IN C'?25
--......;'
- -;"-!l
-- -.,. --!I;;;
-~- . ,.,l •
.,.- "'-'--
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..... -"to ,-\--, -.... -
4 6 8 10VOLTAGE (V)
Date~PaneiT~-Di8J~ Serial N~..;.."i~__ By T/'l::)
: .. 4- l--
,"
-\"- -_:: ,,",'~4-
- .... ,..4--i""'o~ -
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--
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..... ,
-I-, -
.,. .~
-+~_t"
, ...
---
FIGURE 7AFTER SO
THERMAL CYCLES
- --- '__ :+;',!: '':: I::;::
=
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..... . ... -'+'
'-- .,.
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.,...... :n
.- -+---
FORM 11140
oo 2
lIi~~1
1.4
1.2
1.0
0.8 1-__
0.2
14
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87 72
12
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10
71.37 %9.57 %
6.6b13.885.3611. 662.19
.- ---- ....
8
CORRECTIONS
25 DEGREES C AT ONE SUN
PANEL TYPE?HUGHESS.....H?11Voc?6.6Isc'?11.5V AT PlAax?5.3I AT Pllax?18.2 ~
CELLS IN SERIES~PARALLEL?12~6
CELL AREA IN SQ. CM.?98.25WHAT REF USED?PSPCALIBRATED CURRENT AT ONE SUN?10.82REF READING DURING TEST?8.79AMBIENT TEMP IN C?27STANDARD TEMP IN C?25
PANEL TYPE?HUGHESS/N'?14-Voe?6.6Ise?11.7V AT PlDax'?5.3I AT PIUlX?10.25CELLS IN SERIES~PARALLEL?12,6CELL AREA IN SQ. C".?90.25WHAT REF USED?PSPCRLIBRATED CURRENT AT ONE SUN?10.82REF READIHG DURING TEST?8.79AMBIENT TEMP IN C?2.7STANDARD TE"P IN C?2~
Two (2) large size Solar Panels in frames; identified by Solarex as U2and IF3.Two (2) small size Solar Panels in frames; identified by Solarex as Style SX.
DRAWIN:i, SPECIFlCATICN OR EXHIBIT:
Test conducted per Solarex Environmental Test Procedure, Section V, ParagraphA, Thermal Cycle Procedure.
QOANl'ITY of lTEXS TE'Sl'ED:
Four (4) Solar Panels
SEOJRITY CIM>SIFIG.TICN OF I~:
N/A
DATE TEST aMPIEl'ED:
27 November 1982
TEST CCNIXJCTED BY:
Litton Amecom Division
DISJ?a:iITICN OF SPECIMmS:
Returned to Solarex for electrical inspection.
ABSTRACl':At the conclusion of the thermal cycling test, the Solar Panels were visuallyinspected by James Hoelscher (Solarex representative) and witnessed byDean Cohen (Hughes Aircraft representative). The four (4) Solar Panels werereturned to Solarex for electrical inspection.
D229of2Page --=--~MIl30.1.-·Zl
rn AMECOMLitton College Park. Maryland 20740
REPORI' NO.
P.O. NO.
621007-2
30013
DATE -=l.J..7-'D:::.:e:::.:c;;.:;e~m;.:::b:.;:::e.:..r_l=_9.<.::8::;:;;2"___ _
Test Specimen
Four (4) Solar Panels:Two (2) large size panels in frames (#2, #3)Two (2) small size panels in frames (style SX)
Summary
This report certifies that the test specimens identified above havebeen subjected to the thermal cycling test prescribed in SolarexEnvironmental Test Procedure, Section V, Paragraph A, Thermal CycleProcedure. Test start date: 10/18/82. Test completion date:11/27/82.
Test Equipment
Type
TemperatureChamber
Manufacturer
Thermotron
Model No.
F-llO-CHV25/ECA-8
SIN
7996
CalibrationDue Date
1/27/83
NOTE: The test equipment listed above was calibrated as requiredwith traceability to the National Bureau of Standards.Calibration records are maintained on file at this facility.
Test Procedure
The Solar Panels shall be subjected to thermal cycling in accordancewith the attached profile (Figure l), with the chamber temperaturevarying between -40°C and +90 0C. The temperature shall vary approximately linearly with time at a rate not exceeding 1000C/h and witha period not greater than six (6) hours per cycle (from ambient to-40°C to +90 oC to ambient). The module circuitry shall be instrumentedand monitored to verify that no open circuits or ground faults occurredduring the exposure.
Test Results
The thermal cycling test of 150 cycles total was completed at 1335hours on 11/7/82. At 0900 hours on 11/30/82, the four (4) Solar Panelswere removed from the test chamber. A visual inspection was performedby James Hoelscher (Solarex representative) and witnessed by DeanCohen (Hughes Aircraft representative). At the conclusion of thetest, the four (4) Solar Panels were returned to Solarex Corporationfor electrical inspection.
D239of3Page-"""----
AMII30Il(,·azl
rn AMECOMLitton College Park Maryland 20740 DAILY TEST LOG
Two (2) Solar Panels of the Prototype 2 x 4 demonstration model; identified bySolarex as #1 and #4.
DRAWI~, SPECIFICATIOO OR EXHIBIT:
Test conducted per Solarex Environmental Test Procedure, Section V, ParagraphB, Humidity Freezing Test Cycle Procedure.
QUANTITY of ITEMS TESTED:
Two (2)Solar Panels
SECURITY CIASSIFICATIOO OF ITEMS:
N/ A
DATE TEST COO'LETED:
29 October 1982
TEST <nIDUCTED BY:
Litton Arnecom Division
DISPOSITICN OF SPECIMENS:
Returned to Solarex for inspection.
ABS'I'RACl':
At the conclusion of the Humidity Freezing Test (10 cycles) the Solar Panelswere removed from the test chamber. A visual inspection of the two (2)panels was performed by James Hoelscher (Solarex representative) and witnessedby Dean Cohen (Hughes Aircraft representative). The Solar Panels were returned to Solarex Corporation for electrical inspection.
-Page 6 of 9 D26
AMII301l\6-'Z1
rn AMECOMLitton College Park. Maryland 20740
Test Specimen
Two (2) Solar Panels: Ul and U4Prototype 2 x 4 demonstration model
DATE ...:1::..:7:.-::D~e...:.c..:;.em=b::..e:::.::r'___=1;..:9...:.8.;:;;2 _
This report certifies that the test specimens identified above havebeen subjected to the Humidity Freezing Cycling test prescribed inSolarex Environmental Test Procedure, Section V, Paragraph B, HumidityFreezing Test Cycle Procedure. Test start date: 10/19/82. Testcompletion date: 10/29/82.
Test Equipment
Type Manufacturer
Humidity/Temp- Tenneyerature Chamber
Model No.
T-30-UFR-I00550
SIN
4785
CalibrationDue Date
2/24/83
NOTE: The test equipment listed above was calibrated as requiredwith traceability to the National Bureau of Standards. Calibrationrecords are maintained on file at this facility.
Test Procedure
The Solar Panels shall be subjected to the Humidity Freezing testin accordance with the attached profile (Figure 2). The modulecircuitry shall be instrumented to verify that no open circuitsor ground faults occurred during the exposure.
Test Results
The Humidity Freezing test of 10 cycles was completed at 1230 hourson 10/29/82. At the conclusion of the test the two (2) Solar Panelswere removed from the test chamber. A visual inspection was performedby James Hoelscher (Solarex representative) and witnessed by DeanCohen (Hughes Aircraft representative). The Solar Panels were returnedto Solarex Corporation for electrical inspection.
Page _7l.-- of 9D27
rn AMECOMLitton College Park. Maryland 20740 DAILY 1EST LOG
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PAGE 8 OF 9TEST BY: CAt:lt-k<.<$ ~(J/uudiWI'INESSED BY: -----------
/0-'1-84 Il!DATE /0 -..;J..Z - 6"'-DATE ------
<-------------~--------D28AMIS301l11l-aZ)
30345
621008-3
P.O. NO.
REPORI' NO. ----'=="-""---=='---------rn AMECOMLitton College Park. Maryland 20740
17 December J982DATE ____----".............""'"""'.......,/.l.o.l.---,~~ _
CONDITION
85% + 2.5% RH "1~~E£ZINCI--85%,: 2.5% RH-
I~S85 ,..-----
IG I CONTINUE0_
100oC/h MAXIMUM I FOR 10 CYCLESau I0::> I....:£ 25 START OF CYCLE END OF CYCLE.......~............ 0~
:J00
200oC/h~ MO.XIMUM
~0ut-:
-40-i .... 0.51. MINIMUM
-'< 'J
I- 20 MINIMUM "1-· MO.X1MUM----1
TIME(h)
FIGURE 2
HUMIDITY FREEZING CYCLE TEST
Page ~9,,-- of 9D29
....M.30.'.-.2)
rn AMECOMLitton College Park. Maryland 20740
ENVIRONMENTAL TEST REPORT
THERMAL CYCLING TEST
FORSOLAREX CORPORATION1335 Piccard Drive
Rockville, Maryland 20850
APP= BY: ~ (J. arrLENVIFbNMEitrALMANAGER
DATE _-,-/1_'.::...f...·....../ .....3=......~..... _
D30
REPORI' NO.
621007-2/3PAGE 1 OF 3
rn AMECOMLitton College Park Maryiand 20740
Test Specimen
REPORT NO. 621007-2/3
P.O. NO. 30013
DATE ~4;L..;\u.I-"au..nul"_']a;l.,rl...i¥-,......,I.l..;;9u8~3~ _
Four (4) Solar panels~ identified by Solarex as Panels #1, #2,#3, and #4.
Summary
This report certifies that the test specimens identified abovehave been subjected to the thermal cycling test prescribed inSolarex Environmental Test Procedure, Section Vi paragraph A,Thermal Cycle Procedure. Test start date: 9/21/82. Testcompletion date: 10/4/82. Duration of test: fifty (50) cycles.
Test Equipment
TemperatureChamber
!1anufacturer
Therrnotron
Model No.
F-IIO-CHV25/ECA-8
SiN
7996
CalibrationDue Date
1/27/83
NOTE: The test equipment listed above was calibrated as requiredwith traceability to the National Bureau of Standards.Calibration records are maintained on file at this facility.
Test Procedure
The Solar Panels shall be subjected to thermal cycling in accordancewith the attached profile (Figure 1), with the chamber temperaturevarying between -40°C and +90 oC. The temperature shall vary approximately lineraly with time at a rate not exceeding 100oC/h and witha period not greater than six (6) hours per cycle (from ambient to-40°C to +90 oc to ambient). The module circuitry shall be instrumented and monitored to verify that no open circuits or groundfaults occurred during exposure.
Test Results
The thermal cycling test of 50 cycles total was completed on 10/4/82.A visual inspection was performed by a Solarex representative andthe four (4) Solar Panels were returned to Solarex Corporationfor electrical inspection.
v. L. DuganD. G. SchuelerE. L. BurgessJ. W. CampbellM. K. FuentesT. D. HarrisonR. G. LundgrenD. F. MenicucciM. G. ThomasG. J. JonesT. S. KeyH. N. Pos t ( 5 0 )J. W. StevensM. W. EdenburnW. L. Garner (3)M. A. PoundC. M. Ostrander (5)
Dist 9
*u.s. GOVERNMENT PRINTING OFFICE: 1984-0-776-027/4373