2: Wire Sizing For 6815; Wire Requirements For Idp Or Sk Modules - Honeywell Farenhyt Series Installation And Operation Manual

Maximum loop length depends on the wire gauge. See "Maximum wiring distance for SD devices" on page 80 for SD.
7.6.2 Wire Sizing for 6815
The SLC requires use of a specific wire type, depending on mode of operation, to ensure proper circuit functioning. Wire size should be
no smaller than 18 AWG (.075 mm) and no longer that 12 AWG (3.25 mm) wire. The wire size depends on the length of the SLC circuit.
It is recommended that all wiring be twisted-pair to minimize the effects of electrical interference.
Wire Requirements
RECOMMENDED: Twisted-unshielded
pair, 12 to 18 AWG (3.31mm
2
mm ). 50 ohms, maximum per length of
Style 6 & 7. 50 ohms per branch maximum
for Style 4 loop.
Untwisted, unshielded wire, in conduit or
outside of conduit.
Twisted, shielded pair
Note:
• Shields must be isolated from ground
• Shields should be broken at each device
Note:
Maximum total capacitance of all SLC wiring (both between conductors and from any conductor to
ground) should not exceed 0.5 micro farads.

7.7 Wire Requirements for IDP or SK Modules

The SLC can be programmed to operate in IDP or SK mode. While shielded wire is not required, it is recommended that all SLC wiring
be twisted-pair to minimize the effects of electrical interference. Use Table 7.5 to determine the specific wiring requirements for the SLC
Figure 7.1 and Figure 7.2 show how wire length is determined for out & back tap and T-Tap.
The following figures show how length is determined for out and back tap and T-Tap style wiring.
IFP-300 / IFP-300ECS Manual P/N LS10145-001SK-E:B 12/18/2017
Table 7.4 Maximum wiring distance for SD devices
Wire Gauge
22 AWG
18 AWG
16 AWG
14 AWG
Distance in Feet (meters)
12,500 ft. (3,810 m)
2
to 0.82 9,500 ft. (2895.6 m)
6,000 ft. (1,828.8 m)
3,700 ft. (1,127.76 m)
5,000 ft. (1,528 m)
3,700 ft. (,127.76 m)
5,000 ft. (1524 m)
3,700 ft. (1,127.76 m)
Table 7.5 SLC Wiring Requirements for IDP or SK modules
Figure 7.1 Calculating wire run length for a simple out and back
Max. Distance for SD
1500 feet
3900 feet
6200 feet
10,000 feet
12 AWG (3.31 mm
14 AWG (2.08 mm
16 AWG (1.31 mm
18 AWG (0.82 mm
12 to 16 AWG (3.31
18 AWG (0.82 mm)
12 to 16 AWG (3.31 mm
18 AWG (0.82 mm
Wire Type
2
)
2
)
2
)
2
)
2 2
mm to 1.31 mm )
2 2
to 1.31 mm )
2
)
80