NAiS FP0 Series, Hardware Manual

Page: 119 / 173

Wiring FP0
7 - 7 Matsushita Automation Controls
7.3 Grounding
7.3 Grounding
Under normal conditions, the inherent noise resistance is sufficient. However, in
situations of excess noise, ground the instrument to increase noise suppression.
For grounding purposes, use wiring with a
minimum of 2 mm
2
. The grounding
connection should have a resistance of less than 100
•
.
FP0
FP0
CORRECT
Other
device
Other
device
.
Notes
D
The point of grounding should be as close to the FP0 control
unit as possible. The ground wire should be as short as
possible.
D
If two devices share a single ground point, it may produce an
adverse effect. Always use an exclusive ground for each
device.
D
Depending on the surroundings in which the equipment is
used, grounding may cause problems.
<Example>
Since the power supply line (24 VDC and GND terminal) of the
FP0 power supply connector is connected to the frame ground
(F.G.) through a varistor, if there is an irregular potential
between the power supply line (24 VDC and GND) and earth,
the varistor may be shorted.
24 V DC
GND
F.G.
Varistor Varistor (39 V DC)
Power supply lines
Power supply connector
of FP0 control unit
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