Detcon FP-524D-HRT - Manual (Page 14)

Model FP-524D-HRT
FP-524D-HRT Instruction Manual Rev. 0.1 Page 10 of 48
Customer
Wiring
White
Blue
Yellow
Black
Wiring to
LEL Sensor
Figure 11 Sensor Connector PCB
a) Remove the junction box cover and unplug the Transmitter Module. Identify the terminal blocks for
customer wire connections.
b) Observing correct polarity, terminate the 3-conductor 4-20mA field wiring (DC+, DC-, and MA) to the
sensor assembly wiring in accordance with the detail shown in Figure 11.
c) Trim all exposed wire leads if they are not permanently landed in the terminal block.
d) Plug the Transmitter Module into the connector PCB and replace the junction box cover.
NOTE: A 6-32 or 8-32 threaded exterior ground point is provided on most junction boxes for
an external ground. If the Sensor Assembly is not mechanically grounded, an external ground
strap must be used to ensure that the sensor is electrically grounded.
2.7 Initial Start Up
Upon completion of all mechanical mounting and termination of all field wiring, apply system power in the
range of 12-28VDC (24VDC typical) and observe the following normal conditions:
a) FP-524D-HRT display reads “0”, and no fault messages are flashing.
b) A temporary upscale reading may occur as the sensor heats up. This upscale reading will decrease to “0”
% within 1-2 minutes of power-up, assuming there is no gas in the area of the sensor.
NOTE: The 4-20mA signal is held constant at 4mA for the first two minutes after power up.
Initial Operational Tests
After a warm up period of 1 hour, the sensor should be checked to verify sensitivity to combustible gas.
Material Requirements
-Detcon PN 600-610000-000 Splash Guard with integral Cal Port -OR-
-Detcon PN 943-000006-038 Threaded Calibration Adapter
- Detcon PN 942-520124-050 Span Gas; 50% LEL methane/balance Air at fixed flow rate of 200-500cc/min.
NOTE: Do not use calibration gases in Nitrogen background gas mixtures. This will cause