Detcon FP-624C - Manual (Page 23)

Reg40002 Data Lo 07 7 0000 0111
Reg40003 Data Hi 00 0 0000 0000
Reg40003 Data Lo 0A 10 0000 1010
Reg40004 Data Hi 00 0 0000 0000
Reg40004 Data Lo 14 20 0001 0100
Reg40005 Data Hi 05 5 0000 0101
Reg40005 Data Lo 50 80 0101 0000
CRC ## #### ####
CRC ## #### ####
Additional Notes:
The calibration LED will light when the transmitter is sending a response to a Master Query.
Communications are 9600 baud, 8 data bits, 1 stop bit, No parity, half duplex 485.
3.13 D
ISPLAY
C
ONTRAST
A
DJUST
Model FP-624C MicroSafe™ sensors feature a 16 character backlit liquid crystal display. Like most LCDs, character
contrast can be affected by viewing angle and temperature. Temperature compensation circuitry included in the
MicroSafe™ design will compensate for this characteristic, however temperature extremes may still cause a shift in
the contrast. Display contrast can be adjusted by the user if necessary. However, changing the contrast requires that
the sensor housing be opened, thus declassif ication of the area is required.
To adjust the display contrast, remove the enclosure cover and use a jewelers screwdriver to turn the contrast adjust
screw located beneath the metallic face plate. The adjustment location is marked “CONTRAST”. See f igure 7 for
location.
3.14 T
ROUBLE
S
HOOTING
G
UIDE
Sensor Fault
1. Open Sensor – broken wire or contact in sensor.
2. Remove replaceable sensor element and check adjacent pin pairs with ohm-meter. Normal reading is 1-4 ohms
and failed reading is an open circuit.
3. Replace sensor if verif ied as Open Sensor.
Heater Fault
1. Open sensor or drifted heater voltage setting.
2. Check heater voltage setting and re-adjust to target reading. Unplug/replug transmitter to see if Fault clears.
3. Remove replaceable sensor element and check adjacent pin pairs with ohm-meter. Normal reading is 1-4 ohms
and failed reading is an open circuit.
4. Replace sensor if verif ied as Open Sensor.
Signal Fault
1. Zero has drifted too far negative.
2. Re-zero sensor in clean air.
Poor Sensor Performance (Slow Response, Drifting Sensor)
1. Check that correct Heater Voltage is applied to your Sensor.
NOTE: Detcon has two version sensors: C-Style and the J-Style. Each uses a different heater voltage setting.
The C-Style sensor measures 0.9”across the exposed stainless steel sinter face and has a serial number format C??-
###. The C-Style sensor requires 2.7 VDC.
The J-Style sensor measures 0.4”across exposed the stainless steel sinter face and has a serial number format J??-###.
The J-Style sensor requires 2.2 VDC.
2. If heater voltage is incorrect, adjust accordingly for the correct sensor type.
Model FP-624C Combustible Gas Sensor PG.23