Grounding - Panasonic FPS Series User Manual

Installation and Wiring

6.3.1 Grounding

If necessary, ground the instrument to increase the noise resistance.
NOTE
•
For grounding purposes, use wiring with a minimum of 2mm
grounding connection should have a resistance of less than 100Ω.
•
The point of grounding should be as close to the PLC as possible. The
ground wire should be as short as possible.
•
If two devices share a single ground point, it may produce an adverse
effect. Always use an exclusive ground for each device.
PLC
1
Other device (inverter etc.)
2
Risk of short circuits
Depending on the surroundings in which the equipment is used, grounding may cause
problems.
Example1:
Since the power supply lines of the FPΣ and of the FP0 expansion unit (24V DC and 0V
terminal) are connected to the function earth (PE) through a varistor, the varistor may be
shorted if there is an irregular potential between the power supply line and function earth.
24V DC
0V
PE
Power supply line of FP
Unit type
FPΣ C32, C28
FPΣ C24
FP0 expansion unit
80
OK
Σ
or FP0 expansion unit
Varistor
82V
56V
39V
FPΣ User's Manual
2
. The