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DURATECH FINISHANALYZER
MIDAC M2000 FTIRUPGRADE MANUAL
This manual contains additional information concerning the
extraction unit settings,not found in the extraction unit hardware
manual. Please read this manual.
Duratech, Inc.440 N. Commerce Ave.Waynesboro, VA 22980
Web: http://www.cfw.com/~duratechE-Mail: [email protected]
(540) 942-5866FAX (540) 943-5914
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DURATECH FTIR UPGRADE MANUALTABLE OF CONTENTS
REVISION 113099GNE
WARRANTY
1.0 INTRODUCTION
2.0 MIDAC M2000 FTIR SPECTROMETER
3.0 GENERAL SYSTEM INFORMATION
4.0 FTIR SETUP AND CONNECTIONS
5.0 ALIGNMENT
6.0 DURATECH FTIR SOFTWARE
7.0 DURATECH JFOY v2.0 SOFTWARE
8.0 SYSTEM STARTUP
9.0 SCANNING YOUR FINISH OIL
10.0 SELECTING WAVELENGTHS
11.0 SYSTEM SETTINGS, PROCEDURES, AND HINTS
12.0 TROUBLESHOOTING AND MAINTENANCE
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LIMITED WARRANTY - DURATECH FTIR UPGRADE PACKAGE
DURATECH, INC. warrants all products of its manufacture to be
free from defects in material andworkmanship. This warranty is
effective for one year from the date of delivery to the
originalPurchaser.
DURATECH, INC. warrants all other products not of its
manufacture but sold as part of thisDURATECH, INC. system to be
free from defects in material and workmanship. This warranty
iseffective for ninety days from the date of delivery to the
original Purchaser.
Upon prompt notification by the Purchaser, DURATECH, INC. will,
at its option, repair or replaceequipment that proves to be
defective during the warranty period, provided the equipment is
returnedto DURATECH, INC. at the expense of the Purchaser. Parts,
labor and return shipment to thePurchaser shall be at the expense
of DURATECH, INC. Parts used and labor performed duringon-site
warranty service requested by the Purchaser shall be at the expense
of DURATECH, INC.Travel costs shall be at the expense of the
Purchaser.
This warranty shall not apply to defects originating from:
1. Improper maintenance or operation by the Purchaser.2.
Purchaser-supplied accessories or consumables.3. Modification or
misuse by the Purchaser.4. Operation outside the environmental and
electrical specifications for the product.5. Improper or inadequate
site preparation.6. Purchaser induced contamination or leaks.
DURATECH, INC. reserves the right to make changes in design or
construction at any time withoutincurring any obligation to make
any changes whatsoever on units previously purchased. DURA-TECH,
INC. assumes no obligation of any kind with respect to design or
construction of products notof DURATECH, INC. manufacture.
This warranty is expressly made by DURATECH, INC. and accepted
by Purchaser in lieu of all otherwarranties, including warranties
of merchantability and fitness for a particular purpose,
whetherwritten, oral, expressed, implied, or statutory. DURATECH,
INC. shall not be liable for normal wearand tear, nor for any
contingent, incidental or consequential damage or expense due to
partial orcomplete inoperability of its products for any reason
whatsoever.
440 North Commerce AvenueWaynesboro, Virginia 22980
Phone (540) 942-5866FAX (540) 943-5914
e-mail:[email protected]
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1.0 INTRODUCTION
Thank you for purchasing the upgrade package to replace your 980
with the latest in infraredspectrometers, the FTIR. The following
sections will describe the installation and setup of the FTIRand
the associated hardware.
2.0 MIDAC M2000 FTIR SPECTROMETER
The Midac M2000 Series FTIR was chosen for this upgrade due to
its ruggedness and high quality.Before proceeding, please read the
FTIR SPECTROMETER OPERATOR MANUAL. You maydisregard the Software
section, as the Grams/386 and Spectra software packages are not
included.The Installation section of the manual provides
installation instructions and requirements. Connec-tion to the DFA
and cell installation are covered in the FTIR SETUP AND CONNECTIONS
section ofthis manual.
3.0 GENERAL SYSTEM INFORMATION
The FTIR uses a DMA (direct memory address) board that is
installed in the P.C. It does not use anRS-232 interface, like the
980 that it is replacing. Duratech decided the easiest and fastest
way tointerface the data from the DMA board to the JFOY software
was to write an interpreter program.JFOY v2.0 is written for DOS.
All the software drivers and programs for the Midac FTIR were
writtenfor Windows. For this reason, the interpreter program was
also written for Windows 95/98. Theinterpreter’s function is to
communicate with the FTIR through the Windows interface, and to
providethe data to the JFOY software (in DOS). We communicate
between the Windows program and theDOS program via the hard drive.
Each program watches for a file on the hard drive, written by
theother program. We call this “bouncing” the data off the hard
drive. Basically, what the interpreterprogram does is this (see
Figure 1 below):
• When a measurement needs to be taken, the JFOY software
creates a specific file on the harddrive.
• The interpreter watches for this file to appear on the hard
drive.• When the file is seen, the FTIR is commanded to scan.• When
the scan is complete, the data is processed. The 4 wavelengths are
converted to
absorbances and placed in a second file on the hard drive, in
the same order as the 980 wouldhave transmitted them over the
RS-232 cable.
• The JFOY watches for this file, retrieves the four absorbance
values, and processes them asusual.
FTIRSOFTWARE
(WINDOWS 95/98)
HARD DRIVE
Figure 1 - “Bouncing” the data off the hard drive to interface a
Windows program to a DOS program.
JFOYSOFTWARE
(DOS)
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4.0 FTIR SETUP AND CONNECTIONS
If you purchased a new DFA with the FTIR and are not upgrading,
some steps do not apply. Pleaserefer to each step to see it applies
to you. Please do the following to set up your new FTIR:
Remove the 980 (only if upgrading 980 to FTIR) • Remove the flow
cell from the 980 (if you purchased an FTIR cell, remove the tubing
from your
old cell and set the old cell aside).• Turn off the 980, and
unplug the power cord.• Disconnect the RS-232 cable.• Remove the
980 from the bench.
Set Up The New P.C. • Turn off old P.C., disconnect all the
cables.• Install new P.C., and connect all the cables.
Set Up The FTIR • Place the FTIR next to the DFA.• Locate the
tubing pass-thru plate on the rear of the FTIR. Pull on the
clamping pin to release the
top half of the plate.• Feed the cell tubing through this
opening,• Insert the flow cell into the cell holder, and lock in
place with the thumbscrews.• Attach the cell tubing to the cell,
routing the tubing so that it does not interfere with the IR
energy
path. This path is the circular area between the two round
windows on opposite sides of thesample chamber. There is a cable
tie above the left-hand window to secure the tubing, to insurethat
the tubing will stay out of the way. When done properly, only the
cell stand and cell will be inthe IR energy path.
• Replace the tubing plate on the rear of the FTIR, and push in
the locking pin to secure the plate.• Connect the FTIR cable to the
rear of the FTIR and the P.C.• Plug in the power supply and connect
to FTIR.• Turn on the FTIR and allow to warm up for 15 - 30
minutes.
Verifying FTIR Operation We have found that sometimes during
shipment, the FTIR gets knocked out of alignment. This cancause a
repeating “knocking” sound when the FTIR is powered up. A single
“knock” when poweringup is normal. If the FTIR is making unusual
knocking noises, then it may need alignment. There aretwo types of
alignment procedures outlined in this manual: Standard and Gross.
Standard Alignmentis used when the signal strength of the FTIR is
low. Gross Alignment is performed when there is nosignal at all and
the FTIR won’t respond (or there is the constant “knocking”
noise).
To verify FTIR operation and alignment, go to MODE and then
ALIGNMENT in the Duratech FTIRsoftware. The standard (or fine)
alignment steps are covered in the Midac manual on pages
6-14through 6-17 in the Maintenance Section and also under
ALIGNMENT in this manual. For all stepsin the alignment procedure,
the Duratech software is used instead of the software referred to
in theMidac Manual.
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We recommend that you read the Midac manual, Chapter 5 “Theory
of Operation” before youcontinue here. Examine Figure 2, showing
the basic outline of the IR energy and the mirrors:
The two mirrors, M1 & M2, must be exactly perpendicular,
both vertically and horizontally. The twoAllen screws at the front
of the FTIR that are used to adjust the alignment move the FIXED
MIRRORto get it perpendicular to the moving mirror. The moving
mirror moves back and forth slowly. If thealignment is off, the
moving mirror can bump the stops at both ends causing the knocking
noise. Or,it might not be not moving at all. To check the
alignment, go to MODE and then ALIGNMENT in theDuratech FTIR
software. Click on START ALIGNMENT. If the moving mirror is
scanning, you shouldshould see the screen below:
SOURCE
MOVING MIRROR
FIXED MIRROR
TO DETECTOR
BEAM SPLITTER
SAMPLE
M1
M2
Figure 2: Typical Michelson Interferometer
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The previous screen shows an FTIR with good alignment. The shape
in the center is called a“centerburst”. The MIN VALUE and the MAX
VALUE are what we are checking. Notice that the MINpeak can be
larger than the MAX peak (this is normal, the values may be the
same or reversed). Themaximum value of each peak is 32,768. Examine
the LARGER peak value. Midac recommends thatthe signal be about 70%
- 90% of full scale, or between 23,000 and 29,500. A value of
greater than90% may saturate the detector and cause errors in
results.
If your Midac is poorly aligned, you may see something like
this:
As you can see, the centerburst is very small. The (larger) peak
value is far too low for goodoperation. An FTIR with this value
needs a standard (fine) alignment.
NOTE: IF YOU CANNOT DISPLAY THE CENTERBURST, THE FTIR MAY BE TOO
FAR OUT OFALIGNMENT TO PRODUCE ANY SIGNAL AT ALL. THE FTIR WILL NOT
COMMUNICATE WITHTHE COMPUTER IN THIS CASE. GO TO THE “GROSS
ALIGNMENT” PROCEDURE ANDCHECK OPERATION OF THE MOVING MIRROR.
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5.0 ALIGNMENT
The Midac manual shows you how to make the adjustments using the
wrenches. We are showingthe same basic information here. Use these
as a guide. However, with practice you will develop a"feel" for the
procedure that will enable you to quickly achieve good signal
strength. The LARGERpeak value should be higher than 23,000 for
best performance, but no more than 29,500.
This is the section that is in the Midac manual, starting on
page 6-14. We are re-wording it herebecause the software you will
use is not covered in the manual. First, start the Duratech
FTIRSoftware. It is located in the Duratech Folder, or on your
desktop. Under MODE on the menu, selectALIGNMENT. Click on START
ALIGNMENT.
Standard (Fine) Alignment Procedure When making FINE
adjustments, move the wrenches very slowly (only a few degrees).
NOTE: TheMidac manual does not mention this, but when moving ONE
wrench, the other wrench also moves.So when moving ONE wrench, you
should hold the other wrench tightly.
SLOWLY adjust the two Allen wrenches while you observe the
reading displayed beneath theinterferogram. Very fine adjustments
can affect the signal greatly, so it is important to move
thewrenches very gradually. After you adjust the wrenches, pause
for a moment to give the reading achance to stabilize before making
your next adjustment. This procedure may take a long time, untilyou
get the "feel" of the adjustments. Very little movements may make a
large difference!
A. Begin by slowly rotating both wrenches together in a
clockwise direction. If this increases thesignal, continue with
gradual adjustments in the same direction until you reach, then
pass, amaximum value. When the value starts to decrease, back up to
the maximum and proceed to 'C'below.
B. If the first clockwise adjustment caused the signal to fall,
slowly rotate both wrenches counter-clockwise until you reach, and
pass, a maximum value. Once you pass through the maximum, backup
until you reach it again and proceed to 'C' below.
MOVE BOTH CLOCKWISEMOVE BOTH
COUNTERCLOCKWISE
MOVE APART MOVE TOGETHER
A B
DC
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C. Turn the two wrenches in opposite directions (away from one
another) in very small increments.Repeat steps 'A' and 'B' and
observe the signal value. If the value increases, move the wrenches
alittle farther apart and adjust clockwise / counterclockwise to
achieve a maximum signal.
D. If the first adjustment in step 'C' did not increase the
signal strength, turn the two wrenches slightlytoward each other.
Repeat steps "A' and 'B' and check the signal value. If it
increases, repeat untilyou find a new maximum.
When your signal level falls in the satisfactory range, the
mirror is aligned. Remove the Allenwrenches. Replace the adjustment
port cover and put the flow cell back in.
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First, check the operation of the moving mirror: TURN OFF POWER
TO THE FTIR.
#1 Remove the left top cover.
#2 You will see the laser on top of a metal box. Look under the
rear of the laser (the left end) insidethe box, and you will see a
wire coil around a square bar. You should be able to slide the coil
backand forth very easily. The coil is bronze colored. If you look
inside the box the laser is sitting on, youcan see two arms that
rock back and forth as you move the coil. This coil is attached to
the scanningmirror inside the box. When the FTIR is working
properly, this coil should slowly move back and forthabout 3 - 4mm
on the square bar. WHEN YOU FIND THE COIL, GO TO THE NEXT STEP.
#3 TURN ON POWER. Is the coil slowly moving back and forth? If
it is NOT, or if the coil is bangingone or both ends, then the
alignment is very bad. The FTIR may not communicate with the PC if
thealignment is this bad. The Midac FTIR manual does not describe
the next steps. This is somethingthat Duratech found, that helps
the process considerably.
#4 On the side of the box, above the large hole, is a laser
sensor. It is below the front of the laser.There are two small
white wires coming from the sensor and going into the box. It’s
location is shownin the above diagram.
#5 Gently remove the laser sensor. It is in a black plastic
container. Set it on top of the box.
Gross Alignment Procedure
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#6 Turn on the power. You will see one or two laser spots on the
back wall of the FTIR, coming outof the laser sensor hole. One is
fixed, and the other spot moves when you adjust the fixed mirror
withthe wrenches.
HINT: Put a piece of dark paper against the wall to reduce the
laser brightness and glare so itis easier to see the tiny
spots.
#7 Use the wrenches to adjust the fixed mirror as you did
before, and watch the two spots. You wantto get the moving spot
directly on top of the fixed spot, so it looks like there is only
one spot. Thismeans that the two mirrors are very close to being
properly aligned.
#8 When you have the moving spot on top of the fixed spot, put
the laser sensor back in it's hole.The coil should start moving. If
you got the moving spot on top of the fixed spot, the coil should
bemoving slowly back and forth about 3 - 4mm.
HINT: If you cannot clearly see two spots, move the wrenches
until the two spots separate.This way it is easier to get them
lined up.
#9 Go to the STANDARD (FINE) ALIGNMENT PROCEDURE section and
optimize the FTIR.
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6.0 DURATECH FTIR SOFTWARE
The figure below shows the screen of the FTIR software, after a
reference scan of polystyrene.
General:
Wave Number - Shows the current wave number for the VERTICAL red
line.
Center Position - Shows the current center position of the
graph. Use the arrows on either side to scroll the spectrum right
and left. (This is not available when a full spectrum has been
selected. See Options settings below.)
Amplitude - Shows the current amplitude for the HORIZONTAL red
line. If displaying an Absorbance plot, shows Absorbance Units. If
displaying a %Transmission plot, shows %Transmission.
Graph Area - Shows the current scan. Can be either a Reference
Scan or Sample Scan and be displayed in either Absorbance Units or
%Transmission.
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Menu Items Description:
File • Exit - Exits the program
Collect Params • Set Default - Returns all configuration
settings to their default values.
• Gain - Sets gain to AUTO, 1, 2, 4, 8, 16, 32, 64, or 128. The
default value is 1.
• Resolution - Sets the resolution. The resolution setting
affects how much time it takes tocomplete the scan. The default
value is 2. With a setting of 2, it takes about 10 seconds
tocomplete a scan. Higher settings are unusable for the DFA.
However, if you are performingsome routine scans and need a higher
resolution, you may temporarily change this value.
IF YOU DON’T RESET IT TO 2, THE DFA WILL STOP WORKING!!
• Scans - Sets the number of scans that will be averaged. The
default number of scans is 4. TheFTIR will average 4 scans then
report the result. This setting gives more than adequateperformance
for the DFA. Higher settings are unusable for the DFA, as the
increase in time willbe too large. However, if you are performing
some routine scans and need higher sensitivity, youmay temporarily
change this value.
IF YOU DON’T RESET IT TO 4, THE DFA WILL STOP WORKING!!
Mode • Alignment - Sets the FTIR to Alignment mode. This is used
to align the mirrors on the FTIR.
• Analysis - Sets the FTIR to Analysis mode. This is used for
normal operation and when runningscans.
Options • Slave Y to X - Slaves Y slider movement. When
scrolling the “X” slider, the “Y” slider will auto-
matically follow the “X”. This is useful when locating peak
values.
• Spectrum - Selects the minimum and maximum displayed
wavenumbers or microns.
• Test Points - Selects wavenumbers (microns) for your
analytical & reference testing (seeSELECTING WAVELENGTHS
section).
• Units - Sets the displayed units to either microns of
wavenumbers.
Zoom • None - Sets the zoom setting to 1
• X1.5 - Sets the zoom setting to 1.5
• X3 - Sets the zoom setting to 3
• X6 - Sets the zoom setting to 6
Help • About - Gives latest program release version. Check the
Duratech Web page for updates.
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Button Description:
Get Reference - Gets the background spectrum. Used only when
PURE solvent is in the cell or when scanning a polystyrene card
without a cell.
Get Sample - Gets the sample spectrum. Used when a sample is in
the cell or when scanning a polystyrene card without a cell.
Absorbance - Shows the absorbance plot for both reference and
sample spectra.
%Transmission - Shows the %T plot for both reference and sample
spectra.
Clear Plot - Clears the generated plot from the screen.
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7.0 DURATECH JFOY v2.0 SOFTWARE
The software that came installed on the P.C. and with the FTIR
must be used. It has been modifiedto work with the FTIR. If you
have any problems with communication to the DFA ( like “DFA ID
DOESNOT MATCH DISK ID”) you will have to run the factory setup. To
do this, go to F-CONFIG. Be sureyour “caps lock” key is OFF. Type
in ‘irvin’ then press enter. (Just start typing, you won’t
seeanything on the screen.) The factory setup menu should
appear:
Enter your DFA serial number, and select “Y” when asked if you
want to program the serial numberinto the DFA. Enter the rest of
the values as shown above. When you reach the concentrationanalyzer
screen, select “Midac FTIR” as shown below:
When done, operate the JFOY software as before. The FTIR
operations are transparent.
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8.0 SYSTEM STARTUP
The power to the DFA, P.C. and FTIR should be left on at all
times. If you are turning on the P.C. orhad to reset it for any
reason, start the software as follows:
#1 - Start the FTIR program. You can minimize it if you wish, it
will simply run in the background.
#2 - Start the JFOY program.
The software will be located on the Desktop and also in a
“Duratech” folder under the Start Menu.
To run the software from the Desktop, double click on the FTIR
icon to start the FTIR software andthen double click on the FOY
icon to start the JFOY software.
To run the software from the Start Menu, click on the Start
menu, move the mouse arrow up toPrograms, then onto Duratech, and
then click on the FTIR icon. Repeat to start the JFOY software.
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9.0 SCANNING YOUR FINISH OIL
The FTIR software has default values that should work well to
measure DMAC and silicon oil.However, you are free to select your
own wavelengths.
IF SELECTING YOUR OWN WAVELENGTHS, DO NOT USE THE NUMBERS FROM
YOUR 980
The 980’s are not perfectly repeatable unit to unit like FTIR’s.
Follow the instructions below to findappropriate wavelengths:
• Have both JFOY and FTIR running. (Use ALT + TAB to switch
between the two programs.)• In F-Manual, fill a cup and rotate it
under the drain tube.• Press ‘F4 - Drain Cup’ to drain the cup,
placing the pure solvent into the flow cell.• Press ALT + TAB to
switch to the FTIR software.• Click GET REFERENCE and wait for the
spectrum to appear.• Press ALT + TAB to switch to the JFOY
software.• Place a cup with oil or DMAC or both in the turntable,
fill it, and rotate it under the drain tube.• Drain the cup,
placing the sample into the flow cell.• Press ALT + TAB to switch
to the FTIR software.• Click GET SAMPLE and wait for the spectrum
to appear.• Click %TRANSMISSION to view the spectrum.
HINT: To convert wave numbers to microns: MICRONS = 10,000 /
WAVENUMBER
You should find the DMAC peak near 6.0µm (1667 wavenumbers), and
the silicon peak near 8µm(1250 wavenumbers). Zoom in using the x3
scale to place the red line at the peak for best accuracy.
Select a reference where the %T is high, and in a valley. Look
near 5µm (2000 wavenumbers). Youcan use a single reference for both
DMAC and oil, or select a reference next to the base of each ofthe
analytical peaks.
IMPORTANT: The JFOY software only recognizes the “Other
Component” when calibrated as Finish #0. THIS ISTHE ONLY FINISH
LOCATION THAT WILL WORK WITH THE SECOND COMPONENT. Whencalibrating
the second component, enter Finish #0 when prompted. If a
calibration curve exists forFinish #0, DMAC will automatically be
calculated and appear on the printout. If you are upgrading toFTIR,
you already know this. Calibrate the DMAC as usual.
If for any reason you are not allowed to enter Finish #0 when
prompted, the CONFIG.DAT file needsto be modified. Use the
HEADERS.EXE program (if you have it), or simply use DOS’s EDIT to
editthe file. Locate the line:
Denier: standard
and change to:
Denier: lycra
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10.0 SELECTING WAVELENGTHS
From OPTIONS select TEST POINTS. The screen below will
appear:
You can enter your chosen wave numbers in this window. The box
“Finish Component” is for theprimary finish oil of interest, and
the box “Other Component” is for a secondary material in
thesolution that you wish to monitor. NOTE: This window contains a
set of default values thatrepresent Silicon oil as “Finish
Component” and a solvent called DMAC as the “OtherComponent”.
FLOW CELL DISCUSSION: The DFA8980 / FTIR is a system optimized
for measuring two components that are dissolved inperclene.
Perclene itself has a background spectra at shorter wavelengths in
the infrared region. Itis important to be sure that you minimize
the effect of perclene’s background by using a shortpathlength when
testing above 6 - 7 microns. Silicon oil has a peak at
approximately 8µm. Perclenehas a background here also. To see the
background for perclene, do the following:
• Remove the flow cell.• Click GET REFERENCE (using air as
reference).• Insert flow cell and flush with clean solvent.• Click
GET SAMPLE to scan the perclene.• Click %TRANSMISSION to view
perclene's waveform.• Examine the area at 8µm to see how much
background (or “blocking”) perclene has at 8µm.
Typically, we have used a 1mm flow cell for all systems
measuring silicon oil and DMAC to minimizethe perclene background.
These cells were either a Duratech “Variable Pathlength” cell,
usingstandard 13mm x 2mm CaF2 windows, or a Foxboro cell with 22mm
CaF2 windows. Both theDuratech and Foxboro cells have a 3/8”
aperture. However, since we are using an FTIR, we areshipping an
off the shelf FTIR cell with new DFA systems. FTIR cells have a
1/2” aperture to allowmore energy through them. These cells are
available to upgrade FTIR users also. However, the 3/8”aperture
cell has tested satisfactorily for use with the FTIR. We are
shipping the FTIR cell becauseit is an off the shelf item, and uses
standard sized windows.
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11.0 SYSTEM SETTINGS, PROCEDURES, AND HINTS
SYSTEM SETTINGS There is only one system setting on the DFA that
must be changed if upgrading to the FTIR. Thissystem setting is the
SAMPLE PUMP UP TIME, located in F-CONFIG, (under F3 - Extraction
Unit).
When a cup is ready to be tested, the sample pump goes through
the following cycle:
1 - goes down, drawing in the sample.
2 - reaches bottom and starts the SETTLE TIME delay to let the
sample settle in the flow cell.
3 - goes up and discharges the sample to waste.
The DFA orders a reading to be taken when the sample pump goes
up, after the sample has settled.The usual time for the SAMPLE PUMP
UP is 5 seconds. The Duratech DTIR’s reading is readyimmediately;
The Miran 980 and Duratech 980's response is about 4 seconds.
However, the FTIRtakes about 10 seconds for a response. If the
SAMPLE PUMP UP time is only 5 seconds, thismeans that the sample
pump can start the flush (pure solvent) before the reading is
finished.
THEREFORE, PLEASE BE SURE THAT THE SAMPLE PUMP UP TIME IS SET TO
A MINIMUMOF 10 SECONDS. WE RECOMMEND A SETTING OF 15 SECONDS, AS
LONG AS YOUR CYCLETIME ALLOWS IT.
The usual cycle time for the DFA8980 is 2 minutes, which easily
allows a 15 second setting.
PROCEDURES Gain Setting (in Duratech FTIR Software):
After the alignment has been checked and adjusted if necessary,
insert the flow cell and perform thefollowing to insure best
operation of the FTIR:
• Flush the cell with pure solvent.
• Go to ALIGNMENT and start alignment. You will see a reduced
signal from having the cell andsolvent in the path. Stop the
alignment and increase the gain setting (usually a setting a 2 is
fine).Go back to the alignment screen and verify the following:
PEAK VALUE (MAX & MIN) : No larger than 29,500 each. Check
BOTH values! One peak may belarger than the other (this is
normal).
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12.0 TROUBLESHOOTING AND MAINTENANCE
Verify System Operation By Scanning A Polystyrene Card A good
way to verify the operation of the FTIR is to scan a polystyrene
card. This is a standardmethod of verifying the FTIR, as the card
has many identifiable peaks. Included with your FTIR is acard and a
scan of what the waveform should look like. To perform a scan,
remove the flow cell andset it aside, out of the path of the 3”
windows in the cell compartment, then:
• Close cover and wait about 5 seconds for the FTIR to
stabilize.• Click GET REFERENCE. Wait for the background spectrum
to appear.• Open the cover and insert the card. Close the cover.
Wait about 5 seconds, then proceed.• Click GET SAMPLE. Wait for the
background spectrum to appear.• Click %TRANSMISSION to view the
waveform of the polystyrene card.
Now is a good time to familiarize yourself with the ZOOM
settings, the CENTER POSITION arrows,and the scroll bars as
discussed in the DURATECH FTIR SOFTWARE section of this manual.
Slidethe horizontal scroll bar until the red line is at any peak of
the waveform (peaks point DOWN whenviewing %Transmission). You do
not need to use the vertical scroll bar at this time. Thewavenumber
is shown in a box at the top of the screen. You can verify this
measurement byreferencing the diagram below. An example is shown
checking peak #3:
1
2
3
4
5
67
8
9
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“CUSTOM INDUSTRIAL CONTROLS AND EQUIPMENT”
BACK NEXT
Peak Values
PEAK WAVE NUMBER PEAK WAVE NUMBER 1 3027 6 1028 2 2851 7 907 3
1944 8 699 4 1601 9 540 5 1181
Your measured values generally should be within ±6 wavenumbers
of the values above. In somecases you may not be able to obtain the
exact number above (i.e. the display jumps from 1945 to1943). Use
the ZOOM to measure the peaks more accurately. You may also type a
wave number inthe text window to get the desired value.
FTIR Maintenance
The Midac FTIR requires very little maintenance. Once set up, it
should run for a very long timewithout incident. Please read the
“Maintenance” section of the Midac FTIR manual for moreinformation.
However, during shipping, the FTIR may have lost alignment of it’s
fixed mirror. Thisrequires an alignment procedure to be performed
(discussed previously in this manual).
FTIR Flow Cell Maintenance
The optional FTIR flow cell is “off-the-shelf” from Wilmad
except for the spacer. It uses standard19mm diameter x 2mm thick
CaF2 windows. The spacer is 316 stainless steel. To clean the
cell:
• Unscrew the bezel from the front of the cell and remove all
components, noting the order that theycame out.
• Clean windows with a solvent other than perclene that is also
safe for the window material.• Rinse the stainless steel spacer
with the solvent.• Re-insert components in reverse order, being
sure to line up the thin sections of the spacer with
the inlet and outlet holes on the cell body. If possible, place
the spacer so that the thin sectionsblock the smallest portions of
the openings as possible.
• Screw on the clamping bezel being careful not to overtighten.•
Flush the cell 2 - 3 times and inspect for air leaks.
NOTE: Some amount of tiny bubbles is normal in the 1/4” line,
due to the perclene beingpulled through the small holes in the cell
at a fast rate.
Replacement parts can be ordered from Duratech, or directly from
the manufacturer.