Sierra Monitor Corporation 4105 - Manual (Page 7)

Model 4105 Gas Sensor Module (12/02) Page: 4
Instruction Manual
4. OPERATION
4.1 Introduction
Under normal conditions the sensor module does not
require operator or technician intervention. The fol-
lowing are conditions under which the module requires
attention:
- Routine periodic calibration.
- Calibration after a high gas alarm.
- Sensor replacement on a planned schedule or
when a sensor failure occurs.
- Periodic cleaning as necessary.
- Unanticipated maintenance.
4.2 Signal Value
During normal operation the current loop of the sen-
sor module and the controller will be between 4 mA
indicating no presence of gas, and 20 mA indicating
that the full scale concentration of gas is present. The
signal value is proportional to the concentration of
gas present.
Figure 4.1
Transmitter Cover Plate
MODEL 4105-05
H S
2
PPM
Unity SPAN ZERO
FAULT /KEYPAD
CAL
Milpitas, CA
Ph. 408-262-6611
Unity SPAN ZERO
FAULT /KEYPAD
CAL
Milpitas, CA
Ph. 408-262-6611
MODEL 4105-02
Combustibles % LEL