Potential Separation And Terminating Resistance - Honeywell ACS-8 Installation Instructions Manual

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7.1.3 Potential separation and terminating resistance

Potential separation
One non-floating interface must be used for each RS 485 cable. The other interfaces must be floating. The
best position for the non-floating interface, is in the middle of the RS 485 cable. The ACS-8 fitted with the
non-floating interface must have a good ground connection. If this is not the case, another ACS-8 should
be selected instead. A good ground is more important than the central location on the RS 485 cable.
Terminating resistors
The terminating resistors must be placed at the first and the last device of a line. Which device is the first
or last device or any device within the line depends on the type of wiring.
Caution! Malfunction possible!
Star-shaped cabling of the devices is not allowed.
Installation Instructions / ACS-8