Balanced Inputs; Output Relays; Tamper - Gallagher HBUS 16 In 16 Out Board Installation Manual

4.1

Balanced Inputs

Cabling should be a minimum size of 24 AWG (0.2 mm
To ensure correct tamper detection (closed or open circuit), the balanced inputs require 4k7
ohm resistors to be connected as close as possible to the device being monitored.
When the monitored device incorporates a normally-closed tamper switch, it can be wired in
series with resistor R1.
Resistor values can be configured for a HBUS 16 In 16 Out Board in Command Centre (via the
EOL Resistors property page). Refer to the topic "Configuring EOL Resistors for devices" in
the Command Centre Configuration Client Online Help.
4.2

Output Relays

The cabling to and from the relay connectors must be capable of carrying sufficient current for
the device the relay is controlling. Each relay circuit is rated:
3 A at 24 Vdc/ac for a resistive load
•
• 1 A at 24 Vdc/ac for an inductive load
Ensure back EMF snubbing components (a diode or Metal Oxide Varistor) are fitted to inductive
loads to prevent voltage spikes from causing equipment to malfunction.
4.3

Tamper

A centrally located tamper detector provides front and rear optical tamper detection.
Note: To prevent incorrect (or continuous) tamper alarms being generated by HBUS 16 In 16
Out Boards that are not being used for tamper monitoring, a Command Centre operator will
need to open the properties for the HBUS I/O item in Command Centre, click the Status and
Overrides tab and check the Disable Front Tamper and Disable Rear Tamper checkboxes.
3E3473 Gallagher HBUS 16 In 16 Out Board Installation Note | Edition 10 | January 2021
Copyright © Gallagher Group Limited
2 ) for all balanced inputs.
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