Alarm Outputs; System Alerts - Gecko Compact Product User Manual

Alarm Outputs

Gecko recorders built from mid 2016 include an alarm output function. There are two alarm
outputs available. The signal on pin 6 of the comms/alarm connector is connected to pin 4
when Alarm #1 is activated, and to pin 5 for Alarm #2, for the alarm duration.
By default the Gecko's positive power is hard-wired to pin 6, but on request we can modify
the hardware to make pin 6 a user input line that switches to the Alarm outputs. If this
modification is done, the switching circuit is rated to 0.13A at 50VAC or 50VDC, but we can
optionally supply an external box with dual relays rated to 10A @ 250VAC or 30VDC.
Each Alarm can be controlled by one of three processes – Level triggers, STA/LTA triggers,
and System Alerts; or the alarm feature can be turned Off. Simply press the Right button
to cycle through the options for each alarm.
The alarm output has always been set to Normally Open (i.e. the relay closes for the
duration when an alarm is active), but you can now toggle this to be Normally Closed.
The final menu determines how long the alarm stays active after being triggered. If this
value is set to zero, the alarm will continue until it is manually reset from the home screen.

System Alerts

System Alerts enable an alarm to be raised when certain monitored parameters get to a
particular level that may indicate an impending problem with the system.
The values are user-editable, but by default the alert will be raised when the voltage drops
below 11.9V, or the CPU temperature exceeds 55°C, and when storage is below 4%.
A Gecko can optionally operate down to almost 6V, but a voltage this low may damage
some batteries. We suggest using a charge regulator that has a low voltage load disconnect.
The internal temperature of the Gecko CPU can get close to 80°C if the external ambient
temperature gets as high as 70°C, but at typical stations the reading would not exceed
50°C, hence the default alert value of 55.
Alarm Outputs
#1: Level - High
> #2: Level - Low
Normally: Open
Alarm Duration
System Alerts
> Low Voltage
High Temperature
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