Delta VFD-ED Series User Manual

Appendix A. EMC Standard Installation GuideVFD-ED
A-9
A-3-2 Ground Loops
A ground loop occurs when the pieces of equipment are connected to more than one grounding path.
In this case, the ground current may return to the grounding electrode via more than one path. There
are three methods to prevent ground loops:
1. Use a common power circuit
2. Single point grounding
3. Isolate signals, e.g. by photocouplers
Equipment
Cable
Equipment
A B
Earth plane
Equipment
Cable
Equipment
A B
Earth plane
Cable
Very good
Go od
Accompanying cable
In order to avoid “Common Mode Noise”, use parallel wires or twisted pair wiring. Follow this rule and
also avoid long wires, it is suggested to place the two wires as close to each other as possible.
Figure A-7
Figure A-8

Delta VFD-ED Series Specifications

General

Brand	Delta
Model	VFD-ED Series
Category	DC Drives
Language	English