Unit installation

MR-2100/MR-2200 Installation Manual
7
MR-2900
The MR-2900 is a networkable fire alarm panel with both addressable and conventional input
capability.
Refer to the MR-2900/MR-2920 Fire Alarm Control Unit Installation Manual.
MR-2944
The MR-2944 is a network annunciator with Liquid Crystal Display and/or LED Zone display,
general system status lights, and general function keys.
Refer to the MR-2944 Annunciator Unit Installation Manual.
Note: Not to be used for ULC applications.
Testing Circuit Supervision
Use the following procedures in the table below to confirm that SLCs and NACs are supervising for
opens, shorts, and grounds. The right column in this table shows the LEDs that illuminate when an
open, short, or ground occurs on a specific circuit. AUX is supervised for shorts and earths only.
Open (NACs) -- Remove the end-of-line
and make circuit impedance infinite.
Open (SLCs) -- Break the line anywhere in
the loop.
NAC illuminates the Trouble LED and the
NAC Trouble LED flashes
SLC illuminates the Trouble LED
Short -- Apply a zero ohm jumper across
the circuit.
SLC illuminates the Trouble LED
NAC illuminates the Trouble LED and the
NAC Trouble LED flashes
AUX illuminates the Trouble LED
Earth Ground (NACs) -- Place a 10KΩ or
smaller value resistor from the supervised
wiring to Earth Ground.
Earth Ground (SLCs) -- Place a 100Ω or
smaller value resistor from the supervised
wiring to Earth Ground.
If an Earth Ground occurs on any circuit the
Fault and Trouble LEDs both illuminate