In an unsupervised circuit, a cut wire on a sensor wired normally open or a shorted wire on a sensor wired normally closed is not detected as alarm triggers. Supervision enables the Verkada BP41 alarm panel to detect these events and trigger a notification or alarm.

Supervision types

There are 2 types of supervision supported by the BP41 alarm panel:

Single End of Line Resistor (EOLR) (1 resistor)
Double EOLR (2 resistors)

These 2 types of supervision can be applied to sensors wired normally open (NO) or normally closed (NC). Reference resistance values for each type are shown below.

Single EOLR supervision (1000Ω resistors)

Resistance	Normally Closed (NC)	Normally Open (NO)
0 Ω	Shorted circuit; trouble condition	Shorted circuit or closed event; alarm activated
1000Ω	Normal state	Normal state
Infinite Ω	Cut wire or open event; alarm activated	Cut wire; trouble condition

Double EOLR supervision

Resistance	Normally Closed (NC)	Normally Open (NO)
0 Ω	Shorted circuit; trouble condition	Shorted circuit; trouble condition
1000Ω	Normal state	Closed event; alarm activated
2000Ω	Open event; alarm activated	Normal state
Infinite Ω	Cut wire; trouble condition	Cut wire; trouble condition

Wire EOLRs to your BP41 alarm panel

In both circumstances, the resistors are installed at the end of the circuit, as close to the sensor as possible, because installing EOL resistors at the panel inhibits the purpose of supervision.

Single EOLR

Double EOL

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