Specifications

PL-6930 / PL-7930 Series User Manual
4-10
4.2.2 Connecting the Power Supply
This section describes the precautions for supplying a power voltage.
• If the supplied voltage exceeds the PL unit's range,
connect a constant voltage transformer.
• For between the line and ground or between the lines,
select a power supply that is low in noise. If there is an
excess amount of noise, connect an insulating trans-
former.
• When supplying power to the PL unit, please separate
the input/output and operation unit 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 cord must not be bundled or
positioned close to main circuit lines (high voltage,
high current), or input/output signal lines.
• Connect a lightening surge absorber, as shown in the
diagram, to deal with power surges.
• To avoid excess noise, make the power cord short
enough as it can be.
SEE
 Electrical (page2-2)/  Electrical
(page2-4)/
• Use constant voltage and
insulating transformers with
capacities of 200VA or more.
• Be sure to ground the surge
absorber (E1) separately from
the PL unit (E2).
• Select a surge absorber that has
a maximum circuit voltage
greater than that of the peak
voltage of the power supply.
Twisted-pair cord
Twisted-pair cord
Constant
Voltage
Transformer
PL Unit
FG
PL Unit
FG
Insulating
Transformer
Main Power
PL Unit
Power
Input/Output
PL Power
Input/Output
Unit
Main
Power
PL
Power
T1
T2
Power
Input/
Output
Main
Circuit
PL Unit
Input/Output
Unit
Input/Output
Unit
Operation
Unit
PL Unit
FG
E2
E1
Lightening Surge
Absorber