Vision™ OPLC™
Unitronics
7
Relay Outputs
Increasing Contact Life Span
To increase the life span of the
relay output contacts and protect
the device from potential damage
by reverse EMF, connect:
A clamping diode in parallel with each
inductive DC load
An RC snubber circuit in parallel with each
inductive AC load
Power Supply
The controller requires an external 24VDC power supply.
A non-isolated power supply can be used if a 0V signal is connected to the chassis.
You must use an external circuit protection device.
Install an external circuit breaker. Guard against short-
circuiting in external wiring.
Double-check all wiring before turning on the power
supply.
Do not connect either the ‘Neutral or ‘Line’ signal of the
110/220VAC to device’s 0V pin.
In the event of voltage fluctuations or non-conformity to
voltage power supply specifications, connect the device
to a regulated power supply.
Earthing the Power Supply
To maximize system performance, avoid electromagnetic interference by:
Mounting the controller on a metal panel.
Earthing the controller’s power supply: connect one end of a 14 AWG wire to the chassis
signal; connect the other end to the panel.
Note: If possible, the wire used to earth the power supply should not exceed 10 cm in
length. However, it is recommended to earth the controller in all cases.
