NAiS FP Series, Руководство пользователя

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FP
Σ
5.2 Wiring of Power Supply
5 - 11
5.2.2 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
Ω
.
The point of grounding should be as close to the PLC unit 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.
Other device
(Inverter etc.)
CORRECT INCORRECT
Other device
(Inverter etc.)
Figure 37: FP
Σ
Grounding
Note
Depending on the surroundings in which the equipment is used,
grounding may cause problems.
Example:
Since the power supply line of the FP
Σ
power supply connector
is connected to the function earth through a varistor, if there is
an irregular potential between the power supply line and earth,
the varistor may be shorted.
24 V DC
0V
Function
earth
Varistor
FP
Σ
power supply line
24 V DC
0V
Function
earth
Varistor
(39 V)
FP0 exponsion unit
power supply line
82 V: for C32T, C32T2
56 V: for C24R2
Figure 38: Power supply line of FP
Σ
and FP0 expansion unit