Oldham 700 TP Series, Инструкция по эксплуатации

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OLCT 700/710 TP
OLCT 700/710 TP Instruction Manual Rev. C.1 Page 13 of 45
In the absence of fault messages (flashing display), OLCT 700/710 TP display reads “0”. A temporary
upscale reading may occur as the detector heats up. This upscale reading will decrease to “0” ppm within
1-2 minutes of power-up, assuming there is no gas in the area of the detector.
NOTE : The 4-20mA signal is held constant at 4mA for the first two minutes after power up.
2.8.1 Initial Operational Tests
After a warm up period of 1 hour, the detector should be checked to verify sensitivity to H
2
S gas.
Material Requirements
•
PN DET-613-120000-700 OLCT 700/710 Splash Guard with integral Cal Port OR PN DET943-
000006-132 Threaded Calibration Adapter
•
PN 18108087 Span Gas; 25ppm H
2
S in balance Air (10ppm for 0-20ppm range)
•
PN DET-985-241100-321 In-Line Humidifying Tube
NOTE : Do not use H
2
S in Nitrogen background gas mixtures. This will cause significant
reading inaccuracies.
NOTE : Span gas bottles contain 0% humidity and this ultra-low humidity condition will cause
inaccurate readings when used to calibrate a detector. To prevent this error, Oldham prescribes
the use of the In-Line Humidifying Tube.
a)
Connect the In-Line Humidifying Tube between the cal gas cylinder and the detector. The humidifying
tube will introduce the ambient relative humidity into the Cal Gas as it passes through the tube.
b)
Attach the calibration adapter to the threaded detector housing. Apply the test gas at a controlled flow
rate of 0.5l/min max. Allow 1-2 minutes for the reading to stabilize. Observe that during the 1-2
minutes the OLCT 700/710 display increases to a level near that of the applied calibration gas value.
c)
Remove test gas and observe that the display decreases to “0”.
Initial operational tests are complete. Oldham H2S gas detectors are factory calibrated prior to shipment,
and should not require significant adjustment on start up. However, it is recommended that a complete
calibration test and adjustment be performed 16 to 24 hours after power-up. Refer to span calibration
instructions in Section 3.4.