Oldham olct 80, User Manual

Page: 86 / 120

10
– Accessories
80
Replacing the sensor cell
(combustible, oxygen, toxic and XPIR sensors)
A defective sensor should only be replaced using an identical
sensor (same gas, same range).
Replacement frequency
The sensor back needs to be replaced any time it is not possible to perform
zeroing, gas calibration or preventative calibration.
Replacing the sensor
Step Action
1. Gather the following items:
■
New sensor pack.
■
4- and 5-mm hex key.
■
Calibration kit (bottle, hood, etc.).
2.
Block the transmission of alarms within the central system.
3. Disconnect the OLCT 80 from its power source.
4. Unscrew the locking screw from the detector head and rotate the detector head 30°
counter-clockwise.
5.
Unplug the connector and remove the defective detector head.
6. Replace the used detector head with an identical new one.
7. Reverse the procedure to reassemble the device; insert and tighten the locking screw.
8. Restore the signal from the OLCT 80 to the central system.
9.
Reset the OLCT 80 's wear rate to zero as described under Sensor replacement on
page 47.
10. Perform a gas sensitivity test as explained on page 72.
Zeroing and adjusting sensitivity (calibration)
Refer to the instructions under Sensor calibration on page 45.
Cross gas factors for combustible gases
Poison resistant catalytic sensor, type 4F
Gas Methane Pentane Hydrogen
Acetone 1.80 0.90
Acetylene 1.40 0.70
Ammonia 1.00 0.50
Benzene 2.10 1.05
n-Butane 1.80 0.90
Ethane 1.40 0.70
Ethanol 1.60 0.80
Ethylene 1.40 0.70
n-Hexane 2.85 1.40
Hydrogen 1.00
Isopropanol 1.80 0.90
JP-4 3.00 1.50
JP-5 3.10 1.55
JP-8 3.20 1.60
Methane 1.00
Methanol 1.35 0.65
n-Pentane 2.00 1.00