Det-Tronics EQP Fire and Gas Detection/Releasing System - Manual (Page 70)

3-51 14.1 95-8533
Sensor Separation with DCUEX
If the installation requires mounting the sensor in a
different location than the DCUEX, observe the
following guidelines.
There are two (2) methods that can be used to
separate the sensor from the DCUEX:
Preferred Method
1. Disassemble the DCUEX and remove the
transmitter board. (Refer to “Wiring” for
disassembly procedure.) Do not re-assemble at
this time.
2. Mount the transmitter board inside the sensor
separation junction box (remove the existing
board).
NOTE
This assembly can be separated from the
DCUEX by up to 1000 feet using three conductor
18 AWG shielded cable. (Regardless of
separation distance, operating voltage at the
transmitter MUST be at least 18 vdc for proper
device operation.) (See Figure 3-66.)
3. Mount the sensor to the separation junction box.
DO NOT overtighten. Plug the sensor into P2 on
the transmitter board.
4. Use a three conductor 18 AWG shielded cable to
connect P1 on the transmitter board to terminals
2, 3 and 4 on the DCU terminal board (See Figure
3-66). Connect the shield to the ground terminal
in the DCUEX junction box.
5. Connect all external wiring to the terminal wiring
board inside the DCU (if not already completed).
Re-assemble the DCUEX as described in the
“Wiring” section. When completed, it should look
similar to the DCU as shown in Figure 3-60.
6. Inspect the O-ring on the DCU and separation
junction box to be sure that they are in good
condition. Lubricate the O-ring and the threads of
the junction box cover with a thin coat of silicone-
free grease (available from Det-Tronics).
7. Replace the cover on the DCU and separation
junction box.
W R
O N
G
COMMUNICATION MODULE
TRANSMITTER BOARD
STANDOFFS (4)
TERMINAL WIRING BOARD
COMMUNICATION MODULE
SWITCHES ON SAME SIDE
(RIGHT)
TRANSMITTER BOARD
TERMINAL WIRING BOARD
CORRECT ORIENTATION OF TRANSMITTER BOARD
COMMUNICATION MODULE
SWITCHES ON OPPOSITE SIDES
(WRONG)
TRANSMITTER BOARD
TERMINAL WIRING BOARD
INCORRECT ORIENTATION OF TRANSMITTER BOARD
B1570
Figure 3-65—Printed Circuit Boards in Combustible Gas DCU