Auto-Zone Control Systems Auto-Zone Basic Systems Installation & Operation (Version 02C) - Manual (Page 38)

Section 2 Auto-Zone Basic
2-8 Installation and Wiring
Communications Loop
The communications network is a two-wire shielded RS-485 loop. The loop is best con-
nected in a daisy chain configuration, meaning the loop is connected from one controller
to another. It is not necessary to sequentially address the zone controllers in relation to
their location on the loop. Cable must be Belden No. 82760 or equivalent.
Tip: Incorrect wiring of the communications loop is the most common mistake made
during installation. Before beginning installation, write down the wire color
used on each terminal connection and consistently maintain that color code. It is
recommended that a continuous wire run be made between devices. Any time a
splice is made in the cable, you increase your chance of problems.
Caution: Make sure when you are inserting wires into the terminal blocks that
strands of wire do not stick out and touch the next terminal. This could
cause a short or erratic operation.
Note: The loop does not have to follow the controller address sequence.
Caution: If comm loop is not installed in conduit, be careful to position the cable
away from high noise devices like fluorescent lights, transformers,
VFDs, etc. Conduit is not required for comm loop wiring unless re-
quired by local codes.