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Induced circulating current

Induced circulating current

Induced circulating current

(OP)
Hello all, first time poster here but my question has intrigued me enough to join and contribute. I have an overhead 3 phase, 800A, 480vac, ungrounded delta service run in parallel to the main switch with each phase on one messenger wire, run in parallel through the three insulated conductors on said messengers. As is obvious (and bad practice) this induces a current into the messenger wire, what has me surprised is the magnitude, in the order of 200A measured on each messenger. As a check I've measured the service grounding conductor and there is 0A on it. Am I correct in assuming that the current being induced is simply circulating between the 3 messenger cables as a result of the difference in induced potential between each of the three phases at any given time? They are presently bonded at each end, I'm hesitant to remove this connection as I feel the lesser of two safety issues is the current flow, as opposed to a standing voltage between each messenger. Since the system is not grounded from an electrical perspective my assumption is that the current simply circulates throughout the messengers, never seeking a path to ground. Thanks in advance.

RE: Induced circulating current

Your theory sounds correct.  You could ground the messengers at just one end if the induced votlage is a safety concern, for example if the messenger is accessible to untrained people.

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