13
Triple Plus+ and Triple Plus+ IR
Setting Up
IMPORTANT SAFETY NOTICE:
All units fitted with sensors to measure both
%LEL AND %Volume Methane, other hydrocarbons or “flammables”
To avoid potential damage to the pellistor sensor used for measuring % LEL
methane when calibrating the IR or thermal conductivity sensor used for meas-
uring % volume methane, the following precautions must be observed. Failure
to follow this guidance may permanently damage the pellistor sensor, resulting
in unsafe, erroneous readings and the need to replace the sensor. If the guide-
lines are followed the sensor should provide long and reliable service.
Special Calibration Precautions
1. Perform a Zero on the unit in clean mobile air as normal.
2. Apply 2.5 % Volume Methane gas using the flow plate and calibrate
the %LEL flammables sensor to either 50.0% LEL (areas covered by
ISO10156) or 56.8% LEL (areas covered by ATEX / IEC 60079-29-
2007).
3. Prepare to apply two samples of methane gas to the unit in quick
succession: first 6% Volume Methane, and then 50% Volume
Methane. Applying 6% Volume Methane will set the pellistor into save
mode so it will not be damaged by applying higher volume levels of
calibration gas.
4. Stop the flow of 6% Volume Methane and follow it within one or two
seconds with 50% Volume Methane. Avoid the introduction of air, for
example by using a three-way valve.
5. Calibrate the % volume flammables channel as normal and then turn
off the gas supply. DO NOT purge the gas line with air.
6. Remove the flow plate and check that both flammables detectors
return to zero reading.
7. For units calibrated with hydrocarbons other than methane the levels
above should be scaled according to the relevant LEL levels.
TIME
Selecting this will give a display of the form:
CURRENT TIME: 21:48:00
HOUR MINUTE QUIT
Press the key labelled HOUR to increment the hours and the key labelled
MINUTE to increment the minutes until the correct current time is displayed