VESDA by Xtralis
VESDA VLP Product Guide
www.xtralis.com
17
3.3.3
General Purpose Input (GPI) Functions
The input terminal requires a voltage supply between 5V and 30 VDC to operate. The input is isolated from the
system by an opto-coupler device. Connect the GPI + terminal to the positive output and the GPI - terminal to
the ground output of the external device. The GPI can be configured to initiate a number of different actions -
including, by default, a Remote Reset function. The GPI can be configured through the ‘Miscellaneous’ screen
menu of the LCD programmer. Refer to the VESDA LCD Programmer Product Guide for details.
Function
State Change
External Reset
Detector Reset when ≥ 5 VDC is at this
terminal.
Mains OK
The detector monitors the state of the
external power supply and responds to the
following conditions.
Mains OK ≥ 5 VDC at this terminal
Mains Fail ≤ 2 VDC at this terminal
Standby Mode
The detector Isolates and the aspirator
turns OFF when ≥ 5 VDC is at this
terminal
Note:
No Alarms can be generated in
this state
Isolate
The detector isolates when the voltage
rises above 5 VDC and De-isolates when
the voltage falls below 5V.
Use Night-time
Threshold
The detector switches over from day-time
to night-time thresholds when ≥ 5 VDC are
at these terminals.
Reset+ Isolate
While power is applied to the GPI the
detector is isolated. In addition, the
disconnection or connection of power to
the GPI resets the unit.
≥ 5 VDC detector isolates
≤ 2 VDC detector reset
Inverted Reset
This is the reverse of the normal reset
function.
≤ 2 VDC detector reset
≥ 5 VDC normal operating mode
Table 3-5: GPI Functions
Notes:
l
The signal voltage into the GPI terminals must be between 5 to 30 VDC.
l
When the detector is isolated or de-isolated as a GPI function, 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 threshold is configured as a GPI function, it overrides the clock settings for day-
start and night-start.
When using the standby or remote isolate options it is recommended that all displays on VESDAnet are
configured to have the Isolate button disabled. When programming the display through the LCD Programmer
choose Isolate Disabled from the Button Lockout menu.
