Sierra Monitor Corporation 4501-05 - Manual (Page 19)

Model 4501-XX Toxic Gas Sensor Module
Page 15 of 35
6.5 CALIBRATION SUB-MENU
* 4501-03 –
Oxygen Calibration: If area is known to be safe with adequate air flow, you may use the surrounding air as the calibration gas.
If Oxygen levels are unknown, it is recommended to use a Zero Air gas standard.
When calibrating an Oxygen module, there is no zero gas process in the calibration procedure. Only span adjustments can be
made. Normal ambient Air = 20.9% Oxygen.
Begin calibration procedure using the magnet on the Mode key until CALIB is displayed.
Enter to begin procedure. Select cal gas value (20.9), Enter to confirm.
Apply span gas for 3 minutes or use surrounding air if acceptable.
Select Enter when done, and procedure is complete.
NOTE
The Analog output values to be transmitted during the calibration procedure are selected in
the maintenance configuration. Normal 20.9% value provides 17.3 mA.
Function Display Description Reference
M E
 
M E
 
M E
 
M E
 
M E
 
M E
 
M E
 
M E
 
M E
 
M E
 
M E
 
H2S
C 25PPM
Operation: Apply calbration gas.
H2S
CAL-FAIL
Operation: No calibration gas applied, or sensor did not respond
correctly.
(Any)
Operation: Hold magnet over Mode Switch for ten senconds to
abort calibration
Sub C
H2S
WAIT-300
Operation: Five minute time out before sensor is returned to
service.
Enter
H2S
C 25PPM
Banner: Apply 25PPM gas, then enter to calibrate gas
sensor
Sub B
H2S
CXXXPPM
Operation: As gas is applied the reading will increase - wait 3
minutes
Enter
H2S
CAL-OK
Calibration Passed - now remove gas
Mode
H2S
XXXPPM
Default Display
Banner: Apply zero gas, enter when done
Mode
H2S
CALIB:--
Key
Banner: Calibration Aborted
H2S
WAIT-300
Operation: Five minute time out before sensor is returned to
service.
Down
H2S
Adj-SPAN
Operation: User adjustable value
Enter
H2S
25PPM-SP
Operation: Ready for user adjustment
Enter
H2S
10PPM-SP
Banner: Select span, enter when done
Down
H2S
25PPM-SP
Operation: Change Span Gas Value to 25PPM
Sub A
Sub A
Sub B
H2S
CXXX PPM
Operation: Apply calbration gas.
Enter
Mode Function - Calibrate
Enter
H2S
Cal Zero
Banner: Select span, enter when done*
Enter
H2S
ACK
Zero gas setting acknowledged
H2S
CXXX PPM
Banner: Apply span gas, then enter to calibrate gas sensor
Sub-Routines
XXXPPM Default Display
Operation: Confirm area clear of gas, or apply zero air to
sensor.
H2S
10PPM-SP
Table 6 - 1: Calibration