65-2661RK-XX-04 M2A Transmitter Operator’s Manual
21
Start Up
Introducing Incoming Power
1. Complete the installation procedures described earlier in this manual.
2. Verify that all wiring connections are correct and secure.
3. Turn on the incoming power.
4. If necessary, turn on the controller or other monitoring device that is connected to the M2A.
5. The OLED display will indicate the firmware version when the M2A is first powered up and will then count
down a one minute warm-up period before normal operation begins. During normal operation, the display
will indicate the target gas and current gas reading. Verify that the display is indicating the target gas and
current gas reading after the warm-up period is complete and normal operation begins.
NOTE:
Allow the M2A’s detector to warm up for 15 minutes before you continue with the next section,
“Adjusting the Fresh Air Reading.”
Adjusting the Fresh Air Reading
When the M2A is shipped from RKI Instruments, Inc., it is factory calibrated. If a full calibration is desired at
startup, see “Calibration” on page 37.
When the M2A is shipped from RKI Instruments, Inc., it is factory calibrated. If a full calibration is desired at
startup, see “Calibration” on page 37.
Since there is a background of CO
2
in air of typically 300 - 600 ppm (0.03 - 0.06 %volume), it is necessary to use
a calibration kit with a 100% nitrogen cylinder to set the zero signal of an M2A with a low range detector (0 -
5000 ppm or 0 - 5.00% volume). Fresh air can be used to zero an M2A with a high range detector (0 - 50%
volume or 0 - 100% volume).
Non-Intrusive Fresh Air Signal Adjustment
If the M2A is installed in a classified area and non-intrusive zero adjustment 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’s
glass cover directly over 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.
WARNING:
The M2A is not an active gas monitoring device during the fresh air adjustment procedure.
The 4-20 mA output signal will “freeze” at 3.5 mA and all relays will remain in their non-
alarm state while the M2A is in Calibration Mode. The output signal will not indicate current
readings and the relays will not resume operating normally until the M2A is in normal
operation again.
CO2
0.0 %VOL
