Proface APL3000B - Node Box PC - Manual (Page 68)

Chapter 3 Installation and Wiring
3-23
3.3.2 Connecting the Power Supply
This section describes the precautions for supplying a power voltage.
• If the supplied voltage exceeds the PS-A unit’s range,
connect a constant voltage transformer.
• Between the line and ground, select a power supply
that is low in noise. If there is an excess amount of
noise, connect a insulating transformer.
• When supplying power to the PS-A unit, please
separate the input/output and power lines, as shown.
• To increase the noise resistance quality of the power
cord, it is recommended to attach a ferrite core to the
power cord.
• The power supply cable must not be bundled or
positioned close to main circuit lines (high voltage,
high current), or input/output signal lines.
• Connect a lightning surge absorber, as shown in the
diagram, to deal with power surges.
• To avoid excess noise, make the power cord as short as
possible.
SEE 2.1.1 Electrical (page2-2)
• Use constant voltage and
insulating transformers with
capacities of 200VA or more.
• Be sure to ground the surge
absorber (E1) separately from
the PS-A unit (E2).
• Select a surge absorber that has
a maximum circuit voltage
greater than that of the peak
voltage of the power supply.
Constant
Voltage
Transformer
Twisted-pair cord
PS-A Unit
FG
Twisted-pair cord
PS-A Unit
FG
Insulating
Transformer
Main Power
PS-A Unit
Power
Input/Output
PS-A Power
Input/Output
Unit
Main
Power
PS-A
Power
T1
T2
Power
Input/
Output
Main
Circuit
PS-A Unit
Input/Output
Unit
Input/Output
Unit
Operation
Unit
E1
Lightning Surge
Absorber
FG
PS-A Unit
E2