Unitronics Uni-I/O UIS-WCB1, Installation Manual

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UIS-WCB1 Installation Guide
6 Unitronics
Wiring Guidelines
In order to ensure that the device will operate properly and to avoid electromagnetic
interference:

Use a metal cabinet. Make sure the cabinet and its doors are properly earthed.

Use wires that are properly sized for the load.

Use shielded twisted pair cables for wiring High Speed and Analog I/O signals.
Use shielded cables for wiring thermocouple and RTD signals.
In either case, do not use the cable shield as a signal common / return path.

Route each I/O signal with its own dedicated common wire. Connect common wires at
their respective common (CM) points at the I/O module.

Individually connect each 0V point and each common (CM) point in the system to the
power supply 0V terminal, unless otherwise specified.

Individually connect each functional earth point ( ) to the earth of the system
(preferably to the metal cabinet chassis). Use the shortest and thickest wires possible:
less than 1m (3.3’) in length, minimum thickness 14 AWG (2 mm2).

Connect the power supply 0V to the earth of the system.

Earthing the cables' shield:

Connect the cable shield to the earth of the system - preferably to the metal cabinet
chassis. Note that the shield must be connected only at one end of the cable;
typically, earthing the shield at the UIS-WCB1 end performs better.

Keep shield connections as short as possible.

Ensure shield continuity when extending shielded cables.
N
OTE
For detailed information, refer to the document System Wiring Guidelines, located in
the Technical Library in the Unitronics’ website.
Wiring the Power Supply
This module requires an external, regulated 24VDC power supply.

The power supply port is not isolated from the bus; therefore the 0V of the power
supply port must be connected to the HMI Panel’s 0V.
Ignoring this directive may damage the device.
Connect the 24V and 0V terminals as
shown in the accompanying figure.
Wiring the Digital Inputs
All 10 digital inputs share the common point CM1. The digital inputs may be wired
altogether as sink or source.
Inputs I0, I1, I3, and I4 can be configured as either normal digital inputs or as high speed
inputs that can receive high speed pulse signals from sensors or shaft encoders.
Inputs I2 and I5 through I9 can function only as normal digital inputs.