SMC sierra monitor corporation Sentry Instruction Manual - Version 6
CALIBRATION
Page: 49
5.3.1.1 GLOBAL CALIBRATION
Proceed with the following steps to perform Global
Calibration.
Step Activity Display
1 Begin ZERO value read. ENTER TO ZERO
1 2 3 4 5 6 7 8
Press ENTER to start the controller recording the
zero signal value for all modules of the selected
gas type.
2 Complete ZERO value read. APPLY ZERO GAS
ENTER WHEN DONE
The upper display will cycle through all the
applicable module numbers with "00" displayed as
the level.
• Example "1. 00", "2 00" etc.
• If any module has not been previously
calibrated the "00" will be replaced by a "--".
• If any sensor is not known to be in clean air at
this time, go to each such sensor which is to be
calibrated and deliver clean air at 100 cc/min
for three minutes using the apparatus in
Section 5.3.2.
Wait until the display cycles through all module
numbers.
Press ENTER to complete the zero read and the
display will advance to the span prompt.
3 Begin SPAN value read ENTER TO SPAN
1 2 3 4 5 6 7 8
Press ENTER to begin the span process. The top
display begins to cycle through all sensor module
numbers which are configured for the selected
calibration gas. Each module number will show a
"period" immediately after the number and a
numerical concentration display as in the
following example. [1. 00] [2. 00].
4 Apply SPAN gas. APPLY 50% LEL
ENTER WHEN DONE
Apply calibration gas to each sensor which is to
be calibrated using the apparatus in Section 5.3.2.
Use magnetic or non magnetic calibration gas
delivery fitting.
During the time calibration gas is being delivered
the upper display on the controller will continue
to cycle through all applicable module number
s.
The module responding to gas will generally show
an increasing reading on each pass.
5 Complete SPAN gas
application
-
no e
rrors
CALIB COMPLETE
PLEASE WAIT
3:00
Step Activity Display
application - no errors PLEASE WAIT 3:00
When all modules have received calibration gas
press ENTER to indicate completion of the span
process. If all modules have been successfully
calibrated the controller will begin the three
minute time delay before placing modules back on
line
6 Error Conditions - Low
Sensitivity
LOW SENSITIVITY
1 2 3 4 5 6 7 8
If any modules were missed, or if any sensors
failed to respond correctly to the calibration gas
the low sensitivity message will identify those
sensor module numbers. If calibration of the
module was attempted, note the number and plan
corrective action as described in Section 7.
7 Error conditions - Not
Calibrated
NOT CALIBRATED
1 2 3 4 5 6 7 8
Press ENTER again. If all modules have been
successfully calibrated the controller will begin
the three minute time delay before placing
modules back on line. If any modules were
displayed as LOW SENSITIVITY, they will be
displayed again as NOT CALIBRATED. Press
ENTER to acknowledge
8 Return to Operate Mode PRESS ENTER TO
OPERATE MODE
When the time delay is complete the display will
read PRESS ENTER TO OPERATE MODE Press
ENTER and the procedure is complete. Repeat the
process as necessary to recalibrate modules or to
calibrate other gases.
Remove all calibration apparatus from sensors.