RKI Instruments M2 Series - Manual (Page 49)

M2 Transmitter Operator’s Manual 44
NOTE: While in calibration mode, if there is no switch activity for the calibration time-
out period the unit will return to normal operation. See “Viewing & Changing
M2 Parameters” on page 30 for instructions to set the calibration time-out.
NOTE: The following procedure assumes that the oxygen concentration in the
calibration area is not normal, 20.9%, but is oxygen deficient. If a fresh air
environment can be verified, applying zero air to the detector is not necessary
when adjusting the fresh air (span) setting.
1. Connect the calibration kit sample tubing to the calibration cup hose barb.
2. Screw the calibration cup onto the detector.
3. Connect the fixed flow regulator to the calibration cup using the sample tubing.
Non-Intrusive Calibration
If the M2 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 M2’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 M2 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 or zero adjustment
procedure. This feature enables one person to perform a calibration if the detector is
mounted remotely from the M2. When zero air is applied to the M2 during a fresh air
adjustment, the M2 will freeze the display reading at the highest response and the M2 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 M2 during a zero
adjustment, the M2 will freeze the display reading at the lowest response to the calibration
gas. The calibration gas can then be removed and the M2 will continue to display this
reading and retain it in its memory until the zero adjustment procedure is completed.
Adjusting the Fresh Air Setting
1. While in normal operation, press and hold the UP/YES button for 5 seconds to enter
Calibration Mode. Release the button when the following screen appears.
2. If you want to continue with calibration, press and release the UP/YES button to
continue. The display will indicate OXYGEN CAL Mode for a few seconds before
showing FreshAir Adjust?.
If you want to exit Calibration Mode, press and release the DOWN/NO button. The
M2 will indicate Leaving CAL Mode and the M2 will return to normal operation.
3. To continue with adjusting the fresh air (span) reading, press and release the UP/YES
button. ENTER will alternate with FreshAir on the top display line and the current
Calib?
YES/NO