D-Guard
2
57
19.1.2
Table of Functions (identified by silk screen legend on relay board and photo annotations)
Function
Description
24V
Supplies power to the relay board and the detector main circuit board.
Connect to positive side of the power supply.
FB (feedback)
Current loop output signal (sourcing type output).
Connect to an external controller input that has an input shunt sense resistor.
0V
Power supply return.
Connect this to negative side of the power supply.
DG+
Detector board positive power supply output.
Connect to the detector main PCB supply positive input.
DG-
Detector board negative power supply output.
Connect to the detector main PCB supply negative input.
Alarm 1
First alarm relay. Changes state when measured gas level exceeds the alarm 1 threshold
setting.
NC and NO connections apply to normally de-energised relay settings.
For normally energised relays, the function of NC and NO are reversed.
Alarm 2
Second alarm relay. Changes state when measured gas level exceeds the alarm 2
threshold setting.
NC and NO connections apply to normally de-energised relay settings.
For normally energised relays, the function of NC and NO are reversed.
Fault
Normally energised Fault Relay.
De-energises if power to the detector is removed or if detector fault is present.
Loop Jumper
This configures the detector to operate in standalone mode where a system controller is
not present
Siren
Connect to the factory fitted Sounder / Strobe on
D-Guard
2
S
units.
Alarm 1 siren
Install this jumper to enable the siren when Alarm 1 is active (normally de-energised relay
setting only).
Alarm 2 siren
Install this jumper to enable the siren when Alarm 2 is active (normally de-energised relay
setting only).