Wiring a Signaling Line Circuit (SLC)
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AFP-300/AFP-400 Installation PN 50253:C1 05/22/97 2-43
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The total DC resistance from panel to branch end cannot exceed 40 ohms.
Measure DC resistance as shown in Figure 2-59:
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1. Short the termination point of one branch at a time. Measure the DC resistance
from the beginning of the loop to the end of that particular branch.
2. Repeat this procedure for all remaining branches in the SLC.
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The total length of wire (12 AWG) in a two-wire SLC cannot exceed 10,000 feet. Find
the total length of wire in the SLC by summing the wire lengths on each branch of the
SLC. Figure 2-60 shows how to find the total length wire in a typical two-wire SLC:
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