Maintenance
35
Special Bias Voltage for Toxic Gas Sensors
NO and some NH
3
sensors require a special high bias. The bias pins are
located next to the PID sensor socket. Using the sensor puller, move the
stopper block from the “OFF” pins to the “ON” pins. The sensor ID and
bias voltage will be checked during the power on sequence. An error
message appears if the sensors are plugged into the wrong socket, or
if the bias voltage is disabled. Biased sensors require 24 hours on bias
before calibration.
