DC motor grounding conductor sizing
DC motor grounding conductor sizing
(OP)
Please advise how to size grounding conductor for DC motor
fed by rectifier in adjustable speed DC drive. I could not
find a reference in NEC for this case.
fed by rectifier in adjustable speed DC drive. I could not
find a reference in NEC for this case.





RE: DC motor grounding conductor sizing
1. Equipment ground is to be tied to surrounding conductive metals to keep all conductive metallic surfaces at the same equipotential level. The DC part from the speed drive may have a choice depending on the manufacturer instruction manual recommendations. If there is a ground fault detection/indication, then one fault to ground will be detected and annunciated. If there is one DC line grounded, then one shall follow the manufacturer instructions since it may need to be connected to the equipment ground, and a grounding conductor size shall be addressed.
2. To avoid electromagnetic interference, there are usually manufacturer recommendation covering shielding, grounding, circuit separation, conduit runs, etc.
RE: DC motor grounding conductor sizing
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Jacobs Engineering Group Inc.
1041 East Butler Road
Post Office Box 5456
Greenville South Carolina 29606-5456
864·676·6458 Phone 864·676·4789 Fax
E-mail: jason.buda@jacobs.com
Jason W. Buda
Electrical and Control Systems Department
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RE: DC motor grounding conductor sizing
RE: DC motor grounding conductor sizing
In general, a ground conductor equal to the size of the armature conductors would be the best case, but economics may dictate that you try to select a smaller size.
Finally, a star for jbuda54...I would give one to dmkirk but he is not a member.
PS: wasn't 54 the high score on the final in our power class...?