Johnson Controls IFC-1010 Technical Manual page 84

Device Loading
and Isolator
Power Up
Monitor
Modules
M500MJ and
M502MJ Monitor
Modules
84 Hardware Installation—Installing the IFC-1010/2020
Isolator modules are powered from the SLC loop. The internal relay is a
latching-type relay to limit the isolator's power requirements. The contact
will open when power is removed. During power up, the relay contact will
close when the SLC voltage rises above 7 volts. If too many addressable
devices are connected to one isolator, the isolator will never reach 7 volts
and thus remain open (activated) on power up. A maximum load of
25 addressable devices can be connected to an isolator to ensure that the
isolator powers up correctly.
Note: During a short circuit fault condition, the control panel will register
a trouble (INVALID REPLY) condition for each device on the
isolated SLC loop branch or loop segment.
The M500MJ, M502MJ, and M501MJ Monitor Modules are addressable
modules that monitor normally open contact, shorting type alarm initiating
devices. The M502MJ can also monitor conventional two wire smoke
detectors. The supervised M500MJ and M502MJ circuits can be wired as
an NFPA Style B or Style D Initiating Device Circuits; the M501MJ
circuit can be wired Style B only. There is no limit to the number of
contact-type devices installed on a monitor module circuit.
Figure 60 and Figure 61 for M500MJ/M502MJ wiring diagrams and
Figure 59 for the M501MJ wiring diagram.
SLC Loop Connections
Connect the SLC loop to M500MJ or M502MJ Terminals 1 (-) and 2 (+).
The M50xMJ occupies one module address on the SLC loop. Set the
rotary switches on the M50xMJ to the particular SLC loop address
required (each M50xMJ requires a unique module address, 01-99).
NFPA Style B Initiating Device Circuit
Connect the alarm initiating devices to a single two wire circuit. This
circuit cannot be T-tapped or branched in any fashion, and must be
terminated across the last device by a listed End-of-Line Resistor (EOLR).
Connect the circuit to M500MJ/M502MJ Terminals 6 (-) and 7 (+).
NFPA Style D Initiating Device Circuit
Connect the normally open contacts of the alarm initiating devices to a
single four wire circuit. This circuit cannot be T-tapped or branched in any
fashion. No external EOLR is required for Style D wiring. Connect the
four wire circuit to M500MJ Terminals 6 and 9 (-), then 7 and 8 (+).
N10
N19
Refer to