Yaskawa i80M Connecting Manual - Manual (Page 316)

A7. PRECAUTIONS
A7. 1 NOISE TREATMENT
OF OPERATION
Servopack used is a
the effect of or
power transistor in the main circuit. When these transistors are switched,
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(switching noise) may sometimes occur depending on the wiring or
grounding method.
The Servopack incorporates CPU. This requires wiring and treatment to prevent noise
interference. To reduce switching noise as much as possible, the recommended method of
wiring and grounding is shown in Fig. A7. 1.
Grounding Method (Fig. A7. 1)
- -
I
I
I 1 GENERATING
CIRCUIT
Twisted cable
-
L
CASE CASE
LEAD OF
C A S E
MORE
3. 5mm 2
OR
MORE
3. 5mm 2
OR
MORE
ONE POINT GROUNDING
Note
1. Use wires of 35mm
2 or more for grounding to the case (preferably flat-woven copper wire
2. Connect line filters observing the precautions as shown (2) Noise Filter Installation.
3. Use twisted pair leads
Fig. A7. 1 Grounding Method
●
Motor frame grounding
dv
When the motor is at the machine side and grounded through the frame, current
from PWM power through the floating capacity of the motor. T O prevent this effect of cur-
rent, motor ground terminal E (motor frame) should be connected to terminal of Servopack.
of Servopack should be directly grounded.)
●
Servopack SG O V
Noise may remain in the input signal line, so make sure to ground SG O V. When motor wiring
is contained in metal conduits, the conduits and boxes must be grounded.
The above
grounding uses one-point grounding.
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