Johnson Controls Metasys FEC Series Installation Manual page 9

Table 4: Communications bus and supply power terminal blocks, functions, ratings, requirements, and cables
Terminal block/ Terminal
Port label labels
HOT
24~
COM
Note: The SA Bus and FC Bus wiring
recommendations in this table are for MS/TP
bus communications at 38.4k baud. For more
information, refer to the MS/TP Communications
Bus Technical Bulletin (LIT-12011034) for detailed
information about wire size and cable length
requirements for the SA and FC buses.
Function, electrical ratings/Requirements
24 VAC Power Supply - Hot
Supplies 20–30 VAC (Nominal 24 VAC)
24 VAC Power Supply Common (Isolated from all other
Common terminals on controller)
35 VA
Metasys System FEC1611 and FEC1621 Field Equipment Controller Installation Guide
Recommended cable type
0.8 mm to 1.0 mm
(18 AWG) 2-wire
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