Module Grounding; Communication Wiring; Communication Wire Grounding - EngA ENGINEERED AIR base Technical Manual

base

MODULE GROUNDING

The base and CD-XM have a black power connection termination that includes Hot (H), Neutral (N), and
Ground (GND). The GND terminal must be connected to a short green wire securely fastened to unpainted
metal directly below the termination of each and every expansion module.
On the CD-XM, the DJ speed sensor wire shield drain wire must connect to the same unpainted ground
connection used by the CD-XM input power. The communication wire ground should only connect to the base
unpainted ground connection.

COMMUNICATION WIRING

NOTICE:
Correctly wiring the internal Modbus communication network is critical to ensuring stable
operation. Maintain the wiring at least 6" (150mm) away from any high power wiring,
motors, transformers or VFD's.
The base communicates with the expansion module(s) via an internal Modbus communication protocol. The
(pink jacket) wire is specific for Modbus communication: ASTM B33, Twisted pair, 22ga. fully shielded with
drain wire, and plenum rated jacket. An end of line resistor (EOL termination) should not be required due to
the relatively short length of the internal Modbus wiring. Care must be taken to ensure correct polarity.
NOTICE:
For consistency, always wire:

COMMUNICATION WIRE GROUNDING

The communication wire drain should be connected only at the same unpainted ground termination used by the
base panel ground. All expansion module intermediate drain wires must be twisted together tightly and taped
to secure together and isolate from ground. A wire nut or insulated splice connector may also be used. It is
important that these must not be grounded anywhere except at the base ground connection.
IOM74
Red to LmA Black to LmB.
18
A
November 2020 R105