4-3 Wiring Conforming to EMC Directives
Improving Control I/O Signal Noise Resistance
Positioning can be affected and I/O signal errors can occur if control I/O is influenced by noise.
Use completely separate power supplies for the control I/O power supply (especially 24 VDC) and
the external operation power supply. In particular, do not connect the 2 power supply ground
wires.
Install a noise filter on the primary side of the control I/O power supply.
If motors with brakes are being used, do not use the same 24-VDC power supply for both the
brakes and the control I/O. Additionally, do not connect the ground wires. Connecting the ground
wires may cause I/O signal errors.
Keep the power supply for pulse commands and error counter reset input lines separated from the
control I/O power supply as far as possible. In particular, do not connect the 2 power supply
ground wires.
We recommend using line drivers for the pulse command outputs.
Always use twisted-pair shielded cable for the pulse command and error counter reset signal lines,
and connect both ends of the shield cable to frame grounds.
If the control I/O power supply wiring is long, noise resistance can be improved by adding 1-
laminated ceramic capacitors between the control I/O power supply and ground at the drive input
4
section or the controller output section.
For open collector inputs/outputs, keep the length of wires to within 2 m.
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OMNUC G5-SERIES AC SERVOMOTOR AND SERVO DRIVE USER'S MANUAL
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