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ESP-LXD 2-Wire Decoder Control System Installation & Troubleshooting Guide
Loop Configuration
If the installation requires longer wire runs than are possible with the STAR configuration (farther
than 1.65 miles away from the controller) then a LOOP configuration may be used. A LOOP
configuration requires looping the 2-wire path out to the farthest decoder then back to the
controller. In a LOOP configuration, the Critical Path is the distance measured by following the
2-wire path around the loop out to the farthest decoder and back to the controller. The maximum
distance for the Critical Path for a LOOP configuration is 6.61 miles for 14 AWG Maxi Cable and 10.52
miles for 12 AWG Maxi Cable. For metric cable the maximum distance for the Critical Path is 12.0
Kilometers for 2.5 mm² cable.
2-Wire Path Loop Pattern Design
Maximum Critical Path Lengths for 2-Wire Paths
Nominal
Wire Size
Ohms per 1000' or
Ohms per Km (per
conductor)
Max. Length For Critical Path
Star
Loop
Km
Miles
Km
Miles
2.5 mm2
7.5 0hms/Km
3.00
1.86
12.00
7.46
14 AWG
2.58 0hms/1000'
2.66
1.65
10.63
6.61
12 AWG
1.62 0hms/1000'
4.23
2.63
16.93
10.52