circulating currents

Are you talking about a circulating current in an armoured cable's sheath?

If so and you are asking about armoured cables, which you pretty much have to be asking about, as that is the only type of circulating current I can think of, here is what you need to do.

You need to ensure that the armour is only bonded to ground at one point and at one point only.

If the metal of the sheath is connected to ground at any two locations, a sheath current can flow between those two locations. So... You will also need to keep the metal of the armour isolated from ground, usually by wrapping with tape or rubber or some such insulating medium, where they are clipped to their supporting structure along the length of the cable run.

Doing this breaks the circuit path so a circulating current impressed on the sheath by induction can not flow.

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