Spectrex Series 300 Open-Path Gas Detection System - Manual (Page 48)

Spectrex Inc. - SafEye TM 300 Gas Detector Manual – TM 794100, Rev. D, May 2004
40
5.6.3 Detector Terminal Wiring
The detector contains a terminal board consisting of two terminal blocks.
Power Supply:
The input power is supplied to terminal 1. The Return is connected to 2.
Note
Ensure that the detector unit receives a minimum of 18 Volts DC and
does not exceed 32 Volts DC.
Fault Relay:
The Fault Relay is normally open. The SPST relay is at terminal 4 and 5. The
contacts are normally energised closed when the detector is in normal operation.
Alarm Relay:
The Alarm Relay is SPDT Relay. Terminals 6 and 7 are Normally Open and the
contacts are closed when the detector is in the Alarm status. Terminals 7 and 8
are Normally Closed and the contacts are open when the detector is in the Alarm
status.
Accessory Relay:
The Accessory output is Normally Open SPST relay. Its contacts are at terminals
9 and 10. It can be defined per user requirements (See Appendix B.)
Note
To protect the dry contacts from voltage surges when connected to reactive
loads (electric motors, sirens, etc.) connect an appropriate varistor over these
contacts.
4-20mA Output:
Terminals 11 and 12 are used for 4-20mA current output as specified in section
3.7.1 (See Appendix B.)
RS-485 Output:
Terminal 13 and 14 are used for the communication network (See Appendix B.)