M2A-XL Transmitter Operator’s Manual
Chapter 7: Maintenance
•
59
Special Note About Calibrating a ClO
2
Detector
There are two ways to calibrate a ClO
2
detector: using a ClO
2
generator or using a Cl
2
cylinder
and a 0.4 factor.
• If a Cl
2
cylinder is used for calibration, RKI Instruments, Inc. recommends using 2 ppm of
Cl
2
and setting the ClO
2
reading to 0.8 ppm.
• If a ClO
2
generator is being used, the generator’s flow rate should be set to 0.5 LPM.
RKI Instruments, Inc. recommends that 0.5 ppm ClO
2
be used. The steps related to use of
a calibration gas cylinder in the following instructions can be disregarded.
Non-Intrusive Calibration
If the M2A-XL is installed in a classified area and non-intrusive calibration is required, follow the
instructions below, but do not remove the junction box cover. Use the magnetic wand accessory to
actuate the magnetic switches instead of pushing the control switch buttons. To actuate a magnetic
switch and perform the same operation as pressing a control switch button, touch the magnet in
the end of the magnetic wand to the M2A-XL’s glass cover directly above the magnetic switch
you wish to actuate. Touching the glass and removing the wand is the same as pressing and
releasing a button. Touching the glass and keeping the wand in place is the same as pressing and
holding a button.
Calibration Gas Response Memory Feature
The M2A-XL has the capability to “remember” the detector’s response to the calibration gas after
the gas is removed from the detector during the fresh air and span adjustment procedure. This
feature enables one person to perform a calibration if the detector is mounted remotely from the
M2A-XL. When zero air is applied to the M2A-XL during a fresh air adjustment, the M2A-XL
will freeze the display reading at the lowest response and the M2A-XL will continue to display
this reading and retain it in its memory until the fresh air adjustment procedure is completed.
When calibration gas is applied to the M2A-XL during a span adjustment, the M2A-XL will
freeze the display reading at the highest response to the calibration gas. The calibration gas can
then be removed and the M2A-XL will continue to display this reading and retain it in its memory
until the span adjustment procedure is completed.
