Crowcon Triple Plus+ User Manual page 16

Setting Up
modules. The exact list of gases and their corrections are configurable via a PC
using Portables PC software. The default of gas correction factors for flammable
gases with respect to methane and pentane are listed in Appendix 2.
Note: if no table has been downloaded into the instrument then no correction
factor can be selected (the only option is NO CORRECTION).
CALIB
When a calibration is being performed, replace the integral flow plate with the
calibration flow plate so the gas is not being sampled by the pump.
This allows re-calibration of the instrument, which must first have been zeroed in
clean air. You will need Triple Plus+/Plus+ IR aspirator and a supply of Crowcon
calibration gas (see section 7 Maintenance and Calibration). The top line now
displays one of the instrument's gas channels. This display will look like:
CALIBRATE: CH4 (chan. 1)
<< >>
Use the first two keys to select the required gas. Press QUIT to move back up a
menu level, or CAL to select the gas to calibrate. The display will now change to:
CALIBRATE: CH4 = 0
UP DOWN
The actual gas reading is displayed on the top line, and should go up when the
relevant TEST GAS is aspirated over the sensors. When the reading has stabilised
use the UP and DOWN keys to make the reading match the known test gas con-
centration. Now press CAL to actually calibrate the instrument's gain. QUIT can
be pressed to abandon the calibration. If the instrument is calibrated, it will either
respond with CAL SUCCESSFUL or CAL FAILED. If the calibration failed the instru-
ment's gain is not changed, and means that either the gas concentration was not
equal to the value set (check both and repeat) or that the sensor has deteriorated
with use (see section 7 Maintenance and Calibration for sensor replacement).
Note that when calibrating flammable sensors they will always appear in the
CALIB menu as the sensor type they really are without any flammable correc-
tion factor applied. They should also be calibrated as per the gas they really are,
and not as per the gas selected as a flammable correction factor. For example,
if there is CH4 (methane) sensor in an instrument, and a flammable correction
facor is applied so that the instrument reads PRO (propane) then the sensor
would be selected as the CH4 (and not PRO) in the CALIB menu and methane
used to calibrate the sensor.
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QUIT CAL
QUIT CAL
Triple Plus+ and Triple Plus+ IR