AFP-400 Installation
PN
50253
:
A2 03/12/96
2-31
Wire initiating devices which require 24 VDC operating power as shown in the
wiring diagrams below. Refer to the Device Compatibility Document 15378 for
detector and power supervision relays.
Wiring Four-Wire Smoke Detectors
4.7K, 1/2-watt ELR,
part no. 71245
UL-listed 24 VDC
Four-Wire Smoke
Detectors
UL listed
Power
Supervision
Relay
MMX-1
24 VDC Four-Wire
Detector Power
All connections are
supervised and power
limited
Wiring Four-Wire Smoke Detectors (Style B)
1) Connect the Power Supervision Relay coil leads to the last detector base 24
VDC screw terminal.
2) Calculate the maximum allowable resistance in the 24 VDC detector power
wiring as follows:
Rmax = (20.6 - Vom)
(N)(Is) + (NA)(Ia) + (Ir)
Where: Rmax the maximum resistance of the 24 VDC wires
Vom
the minimum operating voltage of the detector or end of line
relay whichever is greater in volts.
N
the total number of detectors on the 24 VDC supply loop.
Is
the detector current in standby.
NA
the number of detectors on the 24 VDC power loop which
must function at the same time in alarm.
Ia
the detector current in alarm.
Ir
the end of line relay current.
MMX-1
24 VDC Four-Wire
Detector Power
UL listed
Power
Supervision
Relay
UL-listed 24 VDC
Four-Wire Smoke
Detectors
Wiring Four-Wire Smoke Detectors (Style D)
All connections are
supervised and power
limited
Style D Wiring Diagram
Style B Wiring Diagram
Overview
Field Wiring