VESDA VLI Product Guide
VESDA by Xtralis
22
www.xtralis.com
3.2.3
Relays
The relays, located on the main processor card, interface to Fire Alarm Control Panels (FACP) to
communicate faults, alarms and isolate states.
Fault and Fire1 Relay Terminals
Fault (Trouble) and Fire1 (Alarm) relay terminals are located on the main board inside the detector.
The Fault relay is energized during normal operation while the Fire relay is only energized when a
Fire is detected. The operation of the relays are summarized in the following table.
Table 3-1: Fault and Fire Relay Operation
FAULT Relay
FIRE Relay
Normal Operation
(Energized)
Fault
or unpowered state
Normal Operation
(De-energized)
Fire
Programmable Relays
The three additional relays can be programmed using Xtralis VSC software or the LCD
Programmer. Refer to the Xtralis VSC Online Help or LCD Programmer Product Guide for details.
3.2.4
Unmonitored General Purpose Input (GPI)
The GPI is a programmable input which can be configured to initiate a number of different actions -
including, by default, a Remote Reset function.
Notes
l
When the detector is isolated or de-isolated via the GPI, the status cannot be changed
through the normal isolate/de-isolate functions of the Display Module or the LCD
Programmer.
l
When the night-time thresholds are invoked via the GPI, it overrides the clock settings for day-
start and night-start.
The GPI requires a voltage supply between 5V and 30 VDC from the connected device in order to
operate. The input is isolated from the system by an opto-coupler device.
3.2.5
Monitored General Purpose Input (GPI) Wiring
Monitored GPI is available in units fitted with the VESDAnet card. It can be used to monitor the
detector power supply.
With monitored GPI, the detector monitors the GPI for open or short circuit faults when the GPI
function is set to any value except None.
When the GPI function parameter is set to external, the detector indicates an external equipment
fault condition by monitoring the line impedance. An End of Line (EOL) resistor is supplied with the
product and must be assembled in parallel with the device to be monitored.
The EOL resistor provides a known termination to the external equipment, this allows the VLI
detector to identify open or short circuits.