10
A100b
JAN 2009
CALIBRATION OF SENSORS
FIG. E
HORN
S
Z
1 2 34 5 6 7 8
ELECTRO CHEMICAL BOARD SHOWN
(SEMI CONDUCTOR IS SIMILAR)
ZERO POT
ADJUSTMENT
SPAN POT
ADJUSTMENT
SENSING
ELEMENT
0-5V DC
O V
V S
REGULATING
VALVE
CALIBRATION GAS
BOOT
SENSING ELEMENT REPLACEMENT
Basic Sensors
The Basic Gas Sensor uses a three pin plug-in element
for Ammonia Sensors and six pin plug-in element for
Halocarbon Sensors which is internally mounted to the
circuit board. To replace, disconnect power and open
the enclosure. The sensing element is removed by hand;
lifting it off the circuit board. Install the new sensor
element by lining up the pins and press firmly into place.
Connect power and allow the sensor element to stabilize
for 24 hours. Recalibrate and install the cover. Note:
Infrared sensing element (CO
2
) is not replaceable.
Standard, Harsh and Explosion Proof Sensors
Standard, Harsh and Explosion Proof Sensing Elements
are externally mounted to the enclosure. To replace,
disconnect power, open enclosure and disconnect cable
wire from the circuit board. Unscrew sensor element
from enclosure. Install new sensor element. Connect
power and allow sensor element to stabilize for 24 hours.
Recalibrate and install the cover.
Extreme Sensors
Extreme Sensing Elements are internally mounted to
the enclosure. To replace, disconnect power, remove
nut and gasket from sensing element at the base of the
unit, open enclosure and disconnect cable wire from the
circuit board. Remove sensor element from enclosure.
Install new sensor element in reverse order. Connect
power and allow sensor element to stabilize for 24 hours.
Recalibrate and install the cover.
