Appendix
AFP-2800/2802 Manual – P/N 11249 11-Mar-08 101
8
8
.
.
5
5
.
.
2
2
A
A
D
D
D
D
R
R
E
E
S
S
S
S
A
A
B
B
L
L
E
E
L
L
O
O
O
O
P
P
C
C
A
A
B
B
L
L
I
I
N
N
G
G
Applies to:
Signalling Line Circuit (SLC) loops. Refer to the SLC Wiring Manual for more detailed specifications and
specific device listings.
Requirements:
Recommended
Cable
1.5 mm
2
TWISTED pair, NOT shielded suitable for up to 1800m (shielded cable
reduces the max distance of the loop and is more expensive and difficult to install)
Max distance
Recommended cable type (unshielded):
3810 m using 3.25 mm
2
Twisted-unshielded pair
2800 m using 2.5 mm
2
Twisted-unshielded pair
1800 m using 1.5 mm
2
Twisted-unshielded pair
1100 m using 0.75 mm
2
Twisted-unshielded pair
Others:
3000 m using 3.25 mm
2
Twisted-shielded pair
300 m using 3.25 mm
2
Untwisted-unshielded cable
Maximum Current 130 mA: LCM-320
100 mA: LEM-320
400 mA max*: Single SLC loop
Maximum resistance 50 ohms (supervised and power-limited). Refer to section 8.7.4
Analog LCM and LEM Terminations for information on loop wiring styles and installation
checks.
Notes: Usage of shielded or flat cable for the SLC loops are not recommended and should be
avoided where possible.
Fire rated cables may be required as per AS1670, AS1668, and AS2118.
Separate 2 core cable to be run for 24VDC power to FZM-1 and FCM-1 modules as
required.
*Max short circuit…circuit will shut down until short circuit condition is corrected.
Floating Shield
Twisted-unshielded wire is recommended. If twisted-shielded pair wire is used in these installations, use a
floating shield to terminate the wire. The following precautions must be met:
• If the SLC is more than 900 m, divide the shield into floating segments of less than 300 m.
• To divide the shield wire into floating segments, cut shield even with jacket and tape as shown:
NOTE: Using shielded wire in applications where it is not recommended will reduce the maximum SLC length. If
shielded wire must be used where not recommended, failing to float the ends will reduce the maximum SLC
length even further.