Det-Tronics EQP Fire and Gas Detection/Releasing System - Manual (Page 105)

14.1 95-8533 5-3
11. Remove the span gas, and return the analog
input to normal.
12. Activate the reed switch. (The red LED blinks for
3 seconds while the reed switch is closed)
13. The calibration is complete. The calibrate LED
turns off.
Note
If the calibration is not completed within 12
minutes, the previous calibration values are
restored and the calibration is logged as
aborted. the calibrate LeD will flash.
Sensor Replacement
wARNING!
the hazardous area must be de-classified prior
to removing a junction box cover with power
applied.
1. Open the junction box cover and press the
Sensor Replacement Switch.
2. The calibrate LED on the communication module
will flash, indicating it is ready for the zero input.
3. Replace the sensor and apply the zero input (4 ma).
4. Activate the reed switch. (The red LED flashes for
3 seconds while the switch is closed.)
5. The communication module records the
uncalibrated value in position one of the
calibration log and calibrates the zero value. (The
calibrate LED stays on steady.)
6. Apply the calibration gas.
7. The calibrate LED flashes when the input
increases.
8. Activate the reed switch. (The red LED flashes for
3 seconds while the reed switch is closed.)
9. The communication module records the
uncalibrated value in the first register of the
calibration log and calibrates the span value.
10. The calibrate LED stays on steady.
11. Remove the span gas and return the analog input
to normal.
12. Activate the reed switch. (The red LED flashes for
3 seconds while the switch is closed.)
13. The calibration is complete. (The calibrate LED
turns off.)
Note
Pressing the Sensor Replacement Switch aborts
calibration and starts over.
Note
Resetting the communication module will abort
the sensor replacement.
CALIBRATION ALGORITHM C
FOR COMBUSTIBLE GAS DCUs AND
AUTOMATIC CALIBRATION OF UNIVERSAL DCUs
CAUTION!
After exposing the H2S sensor to high
concentrations of gas, it should be exposed to
fresh air for at least 30 minutes, and
re-calibrated.
Routine Calibration
1. Apply the zero gas.
2. Activate the reed switch for at least 4 seconds.
(The red LED flashes for 3 seconds while the
switch is activated.)
3. The calibrate LED on the communication module
flashes, indicating it is ready for the zero input.
4. Wait until the calibrate LED stays on steady
(approximately 4 seconds).
Note
the communication module records the
uncalibrated value in the calibration log and
calibrates the zero value during this time.
5. Apply the calibration gas. (The calibrate LED
flashes when the sensor detects gas.)
6. When the sensor input has been stable for 30
seconds, the communication module records the
uncalibrated value in the calibration log, and
calibrates the span value.
7. The calibrate LED stays on steady.
8. Remove the calibration gas.
9. The communication module waits until the sensor
input drops below 4% full scale.