Notifier 3 Relay Board for VGS STS3REL Series Detectors

The 3 relay board (STS3REL) for SMART3/SMARTS series gas detectors provides outputs with voltage-free contacts:

• The first output is associated with Fault and Watch-dog signalling
• The second output can be associated with detector alarm 1 or alarm 2
• The third output can be associated with detector alarm 2 or alarm 3

The board is equipped with a flat cable with connector for insertion into the appropriate connector on the detector base board.

NOTE: when used with SMARTS series detectors the function associated with the 3 relays can be changed in the detector.

Mounting instructions:

• The STS3REL must be fitted with the detector switched off.
• Insert the posts into the holes on the detector base circuit where indicated
• Insert the connector at the end of the flat cable of the 3 relay board into the appropriate connector on the base of the SMART; point the protrusion on the connector towards the inside of the circuit
• Tighten the screws on the posts to secure the relay board. Once assembly is complete, you will notice that the terminal board is facing upwards, i.e. towards the detector terminal board
• Carry out the wiring
• Switch on the detector

The STS3REL board is designed with the aim of being able to be inserted in systems where a SIL2 functional safety level is required. Three steps are required to ensure this:

• The relays must be normally energised
• During installation, a 1.33 A fuse must be connected to the output of each relay
• Verify the function of the relay contacts at least once a year by testing the gas detector and checking the relays for tripping