Chapter 4 - Installation and Wiring
4-11
PL-5910 Series User Manual
4.3.2 Power Supply Cautions
When connecting the PL unit’s AC power terminals, please be aware of the
following:
Constant
voltage
transformer
Twisted-
pair cable
PL
FG
Insulating
transformer
PL
FG
Main power
source
PL
power
source
T1
T2
I/O power
source
PL
I/O
device
I/O
device
Main circuit
power source
Power
device
AC200V
Twisted-pair cable
PL
FG
Lightning surge
absorber
AC
E1
E2
AC 100V
PL
power
source
I/O power
source
PL
I/O
device
Main
power
source
Twisted-
pair cable
• If voltage fluctuations are expected to
vary beyond the specified range,
connect a constant voltage trans-
former.
2.1 General Specifications
• Use a low-noise power supply both
between the lines and between the PL
and its ground. If there is still excess
noise, connect an insulating trans-
former (noise-prevention type).
Be sure any constant or insulating trans-
former used has a capacity of 200VA or
more.
• Wire the power cords of the PL, I/O
devices, and power supply devices
separately.
• Attaching a ferrite core to the power
cord will improve noise immunity.
• Isolate the main circuit (high voltage,
large current) line, I/O signal lines,
and power cord, and do not bind or
group them together.
• To prevent damage from lightning,
connect a lightning surge absorber.
• Ground the lightning surge ab-
sorber (E1) and the PL (E2) sepa-
rately.
• Select a lightning surge absorber
which will not exceed the allow-
able circuit voltage, even when
the voltage rises to the maximum.
