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Johnson Controls, Inc. SLC Wiring Manual —
P/N 51870:G 04/23/2009
SLC Circuits with Isolators
NFPA Style 7 SLC Using an Isolating Device
5.6 NFPA Style 7 SLC Using an Isolating Device
Style 7 operation requires using a combination of isolator detector bases and isolator modules or
isolator modules before and after a non-isolator device. Flanking each device with an isolator
provides fault protection to all other devices on the loop.
•
T-tapping is NOT allowed within the Style 7 wiring configuration.
•
When a non-isolator base or pull station is used, install isolator modules on both sides of
devices.
•
When an isolator base is used in conjunction with an isolator module, install the isolator
module as shown in Figure 9.3.
•
There must be a close-nipple connection between a device and the isolator bases or modules
that protect it.
Figure 5.5 NFPA Style 7 SLC
NOTE:
See Figure 9.3, “Wiring an Isolator Base” on page 50.
S
L
C-style7
is
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SLC Out
SLC Return
Addressable
Detector
Two-wire Isolator
Detector Base
Addressable
Pull Station
Control Panel
IFC-200, IFC-2020/IFC-1010: The first
isolator module on SLC Out and SLC
Return must be contained within the
same enclosure as the FACP, or these
isolator modules must be connected
within 20 ft. (6.1 m) of the FACP
enclosure in conduit.
Isolator
Module
Isolator
Module
Isolator
Module
Isolator
Module
Isolator
Module
Isolator
Module
Isolator
Module
The first isolator module on SLC Out and SLC Return is
optional for IFC-320, IFC2-640/E, IFC-640/E, IFC-300,
IFC-400 and IFC-3030/IFC2-3030 because the panels
provide the functionality.