Johnson Controls Metasys Intelligent Fire Network Technical Manual page 35

Terminating
Resistors
A B
Ports
Network
Node
Remote Building
A B
Ports
Network
Node
A B
Ports
Network
Node
Remote Building
Figure 11: Combination Wiring (NFPA Style 4 Only)
Both point-to-point and bus configurations require end-of-line resistor
termination at each end of the respective circuit, and terminating resistors
are present on all MIBs and repeaters next to the FN circuit terminals.
Whereas a point-to-point circuit has a terminating resistor at each
node/repeater port (Figure 9), a bus circuit spans multiple nodes/repeaters
with termination only at the outer edges of the circuit (Figure 8).
Note: Unused ports may have terminating resistors in place or removed
as desired.
Table 13: On-Board Terminating Resistors
Resistor
RPT-W
RPT-WF
MIB-W
MIB-WF
* Terminating resistors do not apply to fiber optic cable.
A B A B
Ports Ports
Network
Repeater
Node
A B
Ports
Network
Node
Remote Building
Port A
R40
R40
R20
R20
IFC Networking—Metasys Intelligent Fire Network
A B
Ports
Network
Node
Remote Building
A B
Ports
Repeater
combo
Terminating Resistors
Port B
R41
*
R21
*
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