Fire Panel's output is a reversed polarity output.
When the Fire Panel's output is a reversed polarity output, the idle – non alarm
state – that the + output is negative and the – output is positive.
When an alarm occurs at the fire panel, then the output polarity will be + positive
and – negative.
The Fire Panel's output voltage range is 12 to 24 VDC
At the Fire control panel output a 2.2kOhm resistor must be mounted over the
reversed polarity outputs.
MPA2C3 Installation Guide
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