Johnson Controls Metasys VMA1610, Руководство по установке

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Figure 7: Maximum Wire Length by Current and Wire Size
FC and SA Bus and Supply
Power Wiring Guidelines
Table 4 provides information about terminal block
functions, ratings, and requirements.
Table 4 also provides wire size, cable type, and cable
length guidelines for wiring the VMA communication
buses and supply power.
In addition to the guidelines in Table 4 , observe these
guidelines when wiring the SA/FC Buses and supply
power:
• Run all low-voltage wiring and cables separate from
high-voltage wiring.
• All FC and SA Bus cables, regardless of wire size,
should be twisted, insulated, stranded copper wire.
• Shielded cable is strongly recommended for all FC
and SA Bus cables.
• Refer to the MS/TP Communications Bus Technical
Bulletin (LIT-12011034) for detailed information
regarding wire size and cable length requirements for
the FC and SA buses.
Table 4: Communication Bus and Supply Power Terminal Blocks, Functions, Ratings, Requirements, and
Cables
Recommended Cable Type
1 Function, Electrical Ratings/Requirements Terminal Labels Terminal
Block/Port Label
0.6 mm (22 AWG) stranded,
3-wire twisted, shielded cable
recommended FC Bus Communications +
-
FC BUS
2
Signal Reference (Common) for bus
communications COM
Isolated terminal (optional shield drain connection) SHLD
0.6 mm (22 AWG) stranded,
4-wire (2 twisted-pairs), shielded
cable recommended
The + and - wires are one
twisted pair and the COM and
SA PWR are the second twisted
pair of wires.
SA Bus Communications +
-
SA BUS
2
SA Bus Signal Reference and 15 VDC Common COM
15 VDC Supply Power for Devices on the SA Bus SA PWR
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