Circulating current
Circulating current
(OP)
In an offshore platform, if a 200A conductor is connected from the generator house to the switch board. Assuming earthing is done at both ends. How can circulating current arise in the cable?
When was the last time you drove down the highway without seeing a commercial truck hauling goods?
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RE: Circulating current
Is the generator the only source of power? You need two sources for "circulating" current.
Does the current you referring to actually exist or this is a hypothetical question?
Grounding at multiple places can mess up ground fault detection scheme. Is that what you have in mind?
RE: Circulating current
But, the question - as put - has one answer: There will not be any circulating current in a cable that is connected at both ends to the steel frame of an oil rig.
Of course, there are a few prerequisites for this to be true: 1 the steel frame shall be sloidly welded together and 2 there shall not be any appreciable magnetic fields in the loop formed by cable and steel.
Both these prerequisites are fulfilled in your installation.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Circulating current
RE: Circulating current
In addition, there are most likely codes that apply to your installation.
Notwithstanding, there are special exceptions to this rule, the most common being multiple protective grounding used on distribution systems.
Bill
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"Why not the best?"
Jimmy Carter