Thermo Scientific 146i, Инструкция по эксплуатации

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Optional Equipment
Permeation Oven
Thermo Fisher Scientific Model 146 i Instruction Manual 9-5
15. Go to the High Point screen, enter the exact value of the resistor and
press to calibrate the high resistance point.
16. Press to return to the Factory Cal Oven Therm menu.
17. Remove resistor from POJ3 and re-attach the permeation oven.
18. Perform a thermistor calibration using the “Permeation Tube Oven
Calibration” procedure that follows.
Permeation Tube Oven
Calibration
There are two general approaches that can be used to calibrate the
permeation tube oven. The first is to calibrate the temperature indicator
very accurately (to better than 0.02
°
C) and to use a permeation tube whose
weight loss has been previously determined at that temperature.
Note An error of approximately 0.1
°
C corresponds to an error of 1% in
release rate.
The second approach is to note that the thermistors used to measure
temperature are interchangeable to better than
±
0.2
°
C. Thus a 1% resistor
of the proper value (4.369 K
Ω
for 45
°
C) can be used to set the span on the
measurement interface board. The release rate for the permeation tube is
then determined by weight loss in the actual oven being used.
Setting Perm Oven Temperature You can use either of the two calibration methods presented here. One
method involves performing the “Setting Perm Oven Temperature”
procedure and then continuing with the “Setting Temperature with Water
Bath” procedure.
Alternatively, you can perform the “Setting Perm Oven Temperature”
procedure and then continue with the “Setting Temperature with Known
Resistance” procedure.
In either case, use the following procedure for setting the perm oven
temperature.
1. Unplug POJ3 from the measurement interface board. Place a 4.369 K
Ω
resistor across pins 3 and 4 on the board.