72-820 (300) Engcover - Farnell element14 · Model 72-820/72-823 OPERATING MANUAL Table 1. Symbols l than actual temperature measurements. Do not use in a manner not specified by

Infrared Thermometer

72-820

P/N: 110401100914

72-823

Model 72-820/72-823OPERATING MANUAL

Title Page

557791010101111121515151516161617

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Table of Contents

Model 72-820/72-823 OPERATING MANUAL

IntroductionSafety InformationFeaturesDisplayButtons and ConnectorHow the Thermometer works.Operating the Thermometer

Locating a Hot or Cold SpotDistance and Spot SizeField of ViewEmissivityTrigger LockSwitching oC/ oFHOLD

Typical MeasurementsTesting Contactors (Starters)Testing Enclosed RelaysTesting Fuses and Buss ConnectionsTesting Electrical Connections

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17181920

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21212121212222232324242424

Table of Contents Title Page


Scanning Walls for Air Leaks or Insulation DeficienciesTesting BearingsTesting Belts and SheavesChecking Hydronic Radiant Heat ApplicationsMeasuring Grille, Register, or Diffuser DischargeTemperatureChecking for Blockage in Air-To-Air Evaporators orCondensers

Maintenance Changing the Battery Cleaning the Lens Cleaning the HousingTroubleshootingCE CertificationSpecifications Infrared

LaserElectricalPhysicalEnvironmental

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691322

Table Title Page

List of Tables


1. Symbols2. Buttons and Connector3. Surface Emissivity4. Troubleshooting

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7789101111

Figure Title Page

List of Figures


1 Symbols and Safety Markings2 Infrared Thermometer3 Thermometer Display4 Buttons and Connector5 Locating Hot or Cold Spot6 Distance and Spot Size7 Field of View

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Warning


IntroductionThe Model 72-820 Infrared Thermometer (hereafter, the“Thermometer”) can determine the surface temperatureby measuring the amount of infrared energy radiatedby the target’s surface. They have different distance tospot (D:S) figure and different temperature range, detailssee the contents.It features a temperature range of0oF~1000oF and a distance-to-spot ratio of 12:1.

The non-contact infrared thermometer features lowpower consumption design, allowing extended usewithout the need to replace batteries. The highly intuitivedesign allows fast easy temperature measurement forincreased efficiency in use.

The Thermometer may also be powered from a standardcomputer USB port. This can prove very convenient insituations were repeated battery changes are notpractical. The Thermometer will automatically selectbetween battery and USB port power.

Safety Information

A warning identifies conditions and actions thatpose hazards to the user. To avoid electricalshock or personal injury, follow these guidelines:

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Do not point laser directly at eye or indirectlyoff reflective surfaces.Before using the Thermometer inspect thecase. Do not use the Thermometer if it appearsdamaged. Look for cracks or missing plastic.Replace the battery as soon as the batteryindicator appears.Do not use the Thermometer if it operatesabnormally. Protection may be impaired.When in doubt, have the Thermometerserviced.Do not operate the Thermometer aroundexplosive gas, vapor, or dust.To avoid a burn hazard, remember that highlyreflective objects will often result in lower

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Table 1 and Figure 1 show various symbols and safetymarkings that are on the Thermometer and in thismanual.

Explanation

Risk of danger. Important information.

See Manual.

Warning. Laser

Conforms to Standards of European Union

Low battery.

Symbol


Table 1. Symbols

lthan actual temperature measurements.Do not use in a manner not specified by thismanual or the protection supplied by theequipment may be impaired.

Caution

To avoid damaging the thermometer or theequipment under test protect them from thefollowing:

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EMF (electro-magnetic fields) from arcwelders, induction heaters, etc.Static electricity.Thermal shock (caused by large or abruptambient temperature changes – all 30 minutesfrom the Thermometer to stabilize before use).Do not leave the Thermometer on or nearobjects of high temperature.

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Figure 1. Symbols and Safety Markings

FeaturesThe Thermometer includes:

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Single-spot Laser SightingIntelligent USB power sourceBacklit DisplayTwo level white colour Backlit Display (when usingUSB power up, this feature will be on automatically).Current Temperature Plus MIN, MAX, DIF, AVGTemperature Displays/Easy Emissivity SelectorTrigger Lock

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Celsius and Fahrenheit Temperature MeasurementTripod mountIncluded 9V Battery

Thermometer features are shown in Figure 2.

Battery Cover

Display

9V 6F22 Battery

Laser

Trigger

DisplayThe primary temperature display reports the current orlast IR temperature read until the 8-second hold timeelapses.

Figure 2. Infrared Thermometer

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ABCD

C

A

D B


The secondary temperature display reports a choice ofmaximum, minimum, difference between maximum andminimum temperature or average value.

You can toggle through the maximum, minimum,difference and average IR temperatures anytime thedisplay is on. The MAX, MIN, DIF and AV temperaturesare constantly calculated and updated when the triggeris pressed. After the trigger is released, the MAX, MIN,DIF and AV temperatures are held for 8 seconds.

HOLDSCAN

Laser “On” SymbolSCAN or HOLD

o C/ o F Symbol (Cels ius/Fahrenhei t )Primary temperature DisplaySecondary temperature DisplayEmissivity LO, MED, HITemperature values for the MAX, MIN, DIF,AVGLow Battery symbol. Appears when thebattery charge is <4.5V.

Figure 3. Thermometer Display

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Buttons and Connector

Figure 4. Buttons and Connector

Description

Press MODE button to toggle between MAX, MIN,DIF, and AVG options.Press MODE to turn the Thermometer on againand displays the last measurement result.Press to enter set up mode stepping throughEmissivity set up, Trigger Lock and SwitchingoC/

oF set up.

Details refer to the below Emissivity, Trigger Lockand Switching

oC/

oF topics.

Press to turn the display backlight on and off. icon will be on and off also.When the Thermometer enters the setup up mode,press to select an option, details refer to thebelow Emissivity, Trigger Lock and Switching

oC/

oF topics.Press to turn the laser on and off. After laseris on, will be shown.When the Thermometer enters the user setupmode, press to select an option, details referto the below Emissivity, Trigger Lock and SwitchingoC/

oF topics.

After connecting the USB cable, the Thermometerautomatically selects USB power supply and twolevels white colour Backlit Display will be on.

Button /Connector

MODE

SET

USB port

Table 2. Buttons and Connector

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How the Thermometer WorksInfrared thermometers measure the surface temperatureof an opaque object. The Thermometer’s optics senseinfrared energy, which is collected and focused onto adetector. The Thermometer’s electronics then translatethe information into a displayed temperature readingwhich appears on the display. The laser is used foraiming purposes only.

Operating the ThermometerThe Thermometer turns on when you press the trigger. The Thermometer turns off when no activity is detectedfor 8 seconds.

To measure temperature, aim the Thermometer at thetarget, pull and hold the trigger. Release the trigger tohold a temperature reading.

Be sure to consider distance-to-spot size ratio and filedof view. The laser is used for aiming only.

To find a hot or cold spot, aim the Thermometer outsidethe target area. Then, slowly scan across the area withan up and down motion until you located the hot or coldspot. See Figure 5.

Figure 5. Locating Hot or Cold Spot

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As the distance (D) from the target being measuredincreases, the spot size (S) of the area measured bythe unit becomes larger. The spot size indicates 90%encircled energy. The maximum D:S is obtained whenthe Thermometer is 600mm (60 in) form the targetresulting in a spot size of 20mm (2 in). See Figure 6.

Figure 6. Distance and Spot Size

Make sure that the target is larger than the spot size.The smaller the target, the closer you should be to it.See Figure 7.

Figure 7. Field of View

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Emissivity describes the energy-emitting characteristicsof materials. Most organic materials and painted oroxidized surfaces have an emissivity of about 0.95.

If possible, to compensate for inaccurate readings thatmay result from measuring shiny metal surfaces, coverthe surface to be measured with masking tape or flatblack paint (<150 oC / 302 oF) and use the high emissivitysetting. Allow time for the tape or paint to reach thesame temperatures as the surface beneath it. Measurethe temperature of the tape or painted surface.

If you cannot use paint or use tape, then you couldimprove the accuracy of your measurements with theemissivity selector. Even with emissivity selector, it canbe difficult to get a completely accurate infraredmeasurement of a target with a shiny or metallic surface.

The Thermometer allows you to adjust the unit’semissivity for the type of surface before measured.Refer to Table 2. But it is only a typical case. You could

base on your own case and materials to have differentsetting.

To adjust values for emissivity, follow the belowprocedure:

1 .

2 .

3 .

Press SET to select emissivity set up, icon E on thedisplay is blinking. The Thermometer steps throughemissivity set up, trigger lock and switching oC / oF.Press to increase the value by 0.01 or press andhold to access quick setting. The maximum valueis 1.00.Press to decrease the value by 0.0 or press andhold to access quick setting. The minimum valueis 0.10.

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Table 3. Surface Emissivity

Measure SurfaceMETALSAluminumOxidizedAlloy A3003OxidizedRoughenedBrassBurnishedOxidizedCopperOxidizedElectrical Terminal BlocksHaynesAlloyInconelOxidizedSandblastedElectoropolished

Switch Setting

0.2-0.4

0.30.1-0.3

0.30.5

0.4-0.80.6

0.3-0.8

0.7-0.950.3-0.60.15

Measure Surface

Iron CastOxidizedUnoxidizedMoltenIron WroughtDullLeadRoughOxidizedMolydbenumOxidizedNickelOxidizedPlatinumBlackSteelCold-Rolled

Switch Setting

0.6-0.950.20.2-0.3

0.9

0.40.2-0.6

0.2-0.6

0.2-0.5

0.9

0.7-0.9


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Table 3. Surface Emissivity

Measure SurfaceIronOxidizedRusted

NON-METALSAsbestosAsphaltBasaltCarbonUnoxidizedGraphiteCarborundumCeramicClayConcreteCloth

Switch Setting

0.5-0.90.5-0.7

0.950.950.7

0.8-0.90.7-0.80.90.950.950.950.95

Measure SurfaceGround SheetPolished SheetZincOxidized

GlassPlateGravelGypsumIceLimestonePaper (any colour)PlasticOpaqueSoilWaterWood, (natural)

Switch Setting0.4-0.60.1

0.1

0.850.950.8-0.950.980.980.95

0.950.9-0.980.930.9-0.95


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To lock or unlock the trigger, use the followingprocedures:1. Press SET to select trigger lock setting, the will blink.2. Press to select ON or OFF.

When the trigger is locked, the Thermometer will providecontinuous measurement. There is no need to pull thetrigger.

When the trigger is unlocked, the user must pull thetrigger for measurement. When the trigger is released,the Thermometer will hold the measurement resultautomatically.

1. Press SET to choose oC / oF selection mode,2. Press to select oC or oF.

The display will remain activated 8 seconds after thetrigger is released. HOLD appears in the upper middleof the display. When the trigger is pulled again, theThermometer will begin measuring in the last functionselected.

Typical MeasurementsThis section describes a variety of measurements oftenperformed by technicians.

User could select to turn on or off the backlight andlaser whenever you are making readings with theThermometer. But if you are using USB to powerup the Thermometer, the two levels white colourbacklight will be on automatically.Relatively high emissivity normally means emissivitysetting of about 0.95.Relatively low emissivity normally means emissivitysetting of about 0.30.When the emissivity of an object is unknown,


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the user may cover the surface (temperature >150oC)with black electric tape (emissivity of about 0.95). Allowtime for the tape to reach the same temperature as theobject to be measured. Measure and record thetemperature of the tape.Target the Thermometer to the object to be measured,adjust the emissivity setting to make it as the sametemperature as the tape. At this time, the Thermometeremissivity setting is close to the emissivity of the objectto be measured, measurement could be started.

1.

2.3.

4.

Press SET to select emissivity. Press / to selectrelatively low emissivity for bright contacts, or 0.7mid level for darkened contacts.Press MODE to select MAX.Measure line and load side of one pole withoutreleasing trigger.A temperature difference between the line and loadsides of a pole indicate increased resistance ofone point and a contactor may be failing.

1.

2.3.4.5.

Press SET and then press / to set emissivity torelatively low for uninsulated connectors or relativelyhigh for plastic encased relays or for bakeliteenclosed relays or insulated connectors.Press MODE to select MAX.Start to scan.Measure the relay casing, looking for hot spots.Measure electrical connections on relay terminalslooking for hot spots.

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5.

Press SET and then press / to set emissivity torelatively high for paper covered fuse body orinsulated connections.Press MODE to select MAX.Scan the paper covered length of fuse.Without releasing the trigger, scan each fuse.Unequal temperatures between fuses may indicatevoltage or amperage imbalance.Press SET and then press / to set emissivity torelatively low, for metal fuses and caps and insulated


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6.7.

buss connections.Press MODE to select MAX.Scan each end cap on each fuse/

Press SET and then press / to set emissivity torelatively low for uninsulated connectors or bussconnections or relatively high for insulatedconnections.

1.

Scan the conductor, moving toward direction ofelectrical connector (quick connect, wire nut, bussconnection, or lug).

2.

Turn off heating, cooling, and blower.Press SET to select emissivity. Press / to selectemissivity relatively high for painted surfaces orwindow surfaces.Press MODE to select MIN when opposite side ofwall is at lower temperature and or select MAX whenopposite side of wall is at higher temperature.Measure an interior partition wall surface temperature.Do not release the trigger. Record this temperatureas your baseline (or benchmark) for a “perfectly”insulated wall.Face the wall to be scanned. Stand 1.5m away toscan a 5cm spot on the wall.Scan horizontal rows of wall from top to bottom, orhorizontal rows of ceiling from wall to wall. Look forgreatest deviations from baseline temperature toidentify problems. This completes the insulation testscan.

1.2.

3.

4.

5.

6.


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Turn on the blower (no heat, no cooling) and retest. Iftest results with the blower on are different than resultswith the blower off, this may indicate air leaks inconditioned envelope walls. The air leaks are causedby duct leaks that create a pressure differential acrossthe conditioned space envelope.

Warning

To avoid injury when testing bearings:

Do not wear loose clothing, jewelry, or anythingaround neck when working around moving partssuch as motors, belts, blower, and fans.Make sure an electrical disconnect is withinreach and operating correctly and freely.Do not work alone.

Press SET and then press / to select relativelyhigh emissivity.Press MODE to select MAX.Enable motor and allow it to reach steady stateoperating temperatures.Disable the motor if possible.Measure the two motor bearing temperaturesCompare the two motor bearing temperatures.Unequal temperatures or a high temperature canindicate a lubrication or other bearing problem thatis resulting from excess friction.Repeat the sequence for the blower bearings.

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2.3.

4.5.6.

7.


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Press SET and then press / to select relativelyhigh emissivity.Press MODE to select MAX.Enable the motor and allow it to reach a steadystate operating temperatures.Aim the Thermometer at the surface to be measured.Start recording temperatureSlowly move the Thermometer up the belt towardsecond sheave.

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2.3.

4.5.6.

If belt is slipping, sheave temperature will behigh from friction.If belt is slipping, belt temperature will remainhigh between sheaves.If belt is not slipping, belt temperature will reducebetween sheaves.If inner surfaces of sheaves are not a true “V”shape, this indicates belt slippage and willcontinue to operate at elevated temperaturesuntil sheave is replaced.Sheaves must be properly aligned (include “pitch

& yaw”) for belt and sheaves to operate at appropriatetemperatures. A straight edge or taut string, can beused to check alignments.Motor sheave should operate at a temperatureconsistent with blower sheaves.If motor sheave is at a higher temperature at motorshaft than at outer circumference, belt is probablynot slipping.If outer circumference of sheave is at highertemperature than sheave at motor shaft, then beltis probably slipping and sheaves may be misaligned.


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2.3.

4.

Press SET and then press / to select relativelyhigh emissivity.Press MODE to select MAX.To locate radiant heat tubes in floor, temporarilyelevate the loop temperature to create hotter spotsfor identifying tubing runs.Before releasing trigger, press MODE to togglebetween MIN, MAX, DIF floor temperatures andrecord the temperature for future comparison andtrending under similar conditions.

Radiant heat tubes in the floor will normally run parallelto the outside walls. Starting at the floor wall juncture,scan parallel to the wall while moving into the roomaway from the wall. Parallel to the outside wall youshould find parallel isothermal rows indicating thelocation of heat tubes below the surface. Perpendicularto the outside wall, you should find rising and fallingtemperatures at equal distances. High temperaturesindicate you are scanning a heat tube beneath the floorsurface, low falling temperatures indicate a spacebetween the heat tubes.

1.

2.

3.4.

5.

Press SET and then press / to select relativelyhigh emissivity.Aim the Thermometer at the discharge air grille,register, or diffuser.Measure discharge temperature.Release trigger to freeze the temperature readingfor 8 seconds and record this temperature.Grille, register, or diffuser temperature should beequivalent to discharge temperature at the airhandler.


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2.

3.4.5.6.

Remove panels to gain access to coil return bendsor hairpins.Press SET and then press / to select relativelyhigh emissivity for copper tube.Start the refrigeration system.Aim the Thermometer at coil turn bends/hairpins.Start recording temperature.Take temperature of each return bend/hairpin.

All evaporator return bends/hairpins should beat or slightly above evaporator saturationtemperature from the pressure/temperaturechart.All condenser return bend/hairpins should beat or slightly less than condenser saturationtemperature.If a group of return bends/hairpins do not conformto expected temperatures, that indicates ablocked or restricted distributor or distributortube.

Maintenance

To install or change the 9V battery, open the batterycompartment the battery as shown in Figure 2.

Blow off loose particles using clean compressed air.Carefully wipe the surface with a moist cotton swab.The swab may be moistened with water.

Use soap and water on a damp sponge or soft cloth.

To avoid damaging the Thermometer, do NOTsubmerge it in water.

Caution


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ProblemTarget temperature is over rangeTarget temperature is under rangeLow BatteryPossible dead battery1. Low or dead battery2. Ambient temperature above 40oC (104oF)

SymptomOL (on display)-OL (on display)

Blank DisplayLaser does not work

ActionSelect target with specificationsSelect target with specificationsReplace BatteryCheck and / or replace battery1. Replace battery2. Use in area with lower ambient temperature.

Table 4. Troubleshooting

The Thermometer conforms to the following standards: l EN61326-1 EMC l EN60825-1 SafetyCertification testing was conducted using a frequency range of 80 to 100MHz with instrument in three orientations.

Troubleshooting

CE Certification


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Measurement Range(72-820)---------------------------------------------18oC to 550oC (0oF to 1022oF)Measurement Range(72-823)-------------------------------------------- -32oC to 650oC (-25oF to 1200oF)Spectral Range -------------------------------------------------------------- 8 to 14 micronsAccuracy ---------------------------------------------------------------------- 1.8% or (1.8oC/4oF) Temperature than less 0oC , Accuracy add to 1oC(2oF)

(Assumes ambient operating temperature of 23 to 25oC (73 to 77oF))Repeatability ----------------------------------------------------------------- 0.5% of reading or 1oC/2oFResponse Time (95%) ----------------------------------------------------- 250msDistance to Spot (D:S)(72-820) -------------------------------------------12:1Distance to Spot (D:S)(72-823) -------------------------------------------20:1Emissivty Adjustment ------------------------------------------------------ 0.10~1.00Display Resulation ---------------------------------------------------------- 0.1oC (0.1oF)

Sighting --------------------------------------------------------------------------- Single point laserPower --------------------------------------------------------------------------------- Class 2 (II) operation; Output <1mV, wavelength 630 to 670mm

Power Supply -------------------------------------------------------------------- 6F22 9V BatteryPower Consumption ------------------------------------------------------------ At least 30 hours battery life (Alkarine), At least 10 hours battery life (General Purpose)

Specifications


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Weight ----------------------------------------------------------------------------- 0.322kgSize ---------------------------------------------------------------------------------17.69cm (H) x 16.36 cm (L) x 5.18cm (W)

Operating Temperature Range ---------------------------------------------- 0oC to 50oC (32oF to 120oF)Relative Humidity ----------------------------------------------------------------0 to 75% noncondensingStorage Temperature ---------------------------------------------------------- -20oC to 65oC (-4oF to 150oF)


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This operating manual is subject to change without notice.

** END **

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Copyright 2007 Tenma Test Equipment.All rights reserved.

Tenma Test Equipment405 S. Pioneer Blvd.Springboro,Ohio 45066www.tenma.com

72-820 (300) Engcover - Farnell element14 · Model 72-820/72-823 OPERATING MANUAL Table 1. Symbols l than actual temperature measurements. Do not use in a manner not specified by

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