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11 Appendix
When the leakage current generated by the servo drive triggers the RCD to act, take the following
measures:
■
Increase the rated action current of the RCD.
■
Replace the original RCD with a time-delay type-B RCD.
■
Reduce the carrier frequency.
■
Shorten the length of the output drive cables.
■
Wind the ferrite core around the power cables (PE cable excluded). Recommended RCD brands are
Chint and Schneider.
11.1.8 Solutions to Common EMC Problems
The servo drive generates strong interferences. Although EMC measures are taken, interference may still
exist due to improper wiring or grounding during use. When the servo drive interferes with other devices,
adopt the following solutions.
Table 11-7
Solutions to common EMC interference problems
Interference Type
Solution
RCD tripping
◆
Reduce the carrier frequency without compromising the performance.
◆
Shorten the servo drive cable length.
◆
Wind the ferrite core around the power cables (PE cable excluded).
◆
For tripping at the moment of power-on, disconnected the capacitor that carries
larger capacity (disconnect the grounding end of the external or internal filter and
the grounding end of the grounding Y capacitor of the input terminal).
◆
For tripping during running or enabling, take leakage current
suppression measures (install a leakage current filter, or install a safety capacitor
and wind the ferrite core, or wind the ferrite core).
Interference generated
during running
◆
Connect the motor housing to the PE terminal of the servo drive.
◆
Connect the PE terminal of the servo drive to the PE terminal of the mains power
supply.
◆
Route the power cables (main circuit cables， power cables,
and
regenerative resistor cables), control cables, and signal cables through different
routes.
◆
Wind the ferrite core around the power cables (PE cable excluded).
◆
Install a capacitor to the interfered signal port or wind the ferrite core around this
port.
◆
Install a matching resistor between the communication cable source and the load
end.
◆
Add an auxiliary reference ground wire if the differential cable pair are used for
communication.
◆
Adopt shielded cables as communication cables
◆
Apply additional common-ground connection between devices and
cabinets.