Feedback From The Drive; Hardware Installation; Wiring; Connections - ABB ACS 400 User Manual

Chapter 3 – Installation
Feedback from the
drive

Hardware Installation

Wiring

Connections

3-2
The Metasys can read any Analog and Digital
Input point back from the drive. Each one of the
Input points on the drive has a predefined
meaning, which is described in Chapter 4 –
Programming in this manual.
The N2 Bus network is based upon the
industrial RS-485 standard. The RS-485
connection is made using a shielded, twisted
pair cable.
On the N2 Bus for the ACS/ACH 400 drives,
the wiring connections described below are
recommended. This connection method
ensures minimal noise on the network while
keeping the connections simple and affordable.
The N2 Bus should be wired using Belden 9842
or equivalent. Belden 9842 is a dual twisted,
shielded pair cable with a wave impedance of
120 W. One of these twisted shielded pairs is
used for the RS-485 link. One of the wires in
the other pair is used for the logical ground,
leaving one wire unused. For details, see the
diagram Figure 3-1 "Communication wiring for
ACS/H 400 Drives".
The RS-485 link is a daisy-chained bus, without
dropout lines. The RS-485 link should also be
terminated on both physical ends of the wire to
reduce the noise on the network.
The network should be connected according to
the following diagram. In Figure 3-1
"Communication wiring for ACS/H 400 Drives"
the termination resistors are disconnected.
ACS/ACH 400 Direct N2 Bus Interface