Turning this new heater on jumped the leakage current from 1.8mA to what’s on the screen.


Well, only when the clamp was left as shown. Once raised to a level position, the display dropped to 7mA.
Hmm!!
How well do the jaws on your clamp close when hanging off a cable like that ?
- I suspect that both 1/4A and 7mA are inaccurate and are more of a representation of neither the live nor neutral currents being centrally positioned (nor equally off centre) in the core, and the cancellation of the magnetic fields getting a few percent out of kilter - perhaps more of the flux from the neutral escaping through the gap in the jaws, or is the steel getting magnetically non uniform and needs de-gaussing.
How much current is the heater taking - i.e, what % imperfection in the cancellation are we talking about ?
Mike.
Hmm!!
How well do the jaws on your clamp close when hanging off a cable like that ?
- I suspect that both 1/4A and 7mA are inaccurate and are more of a representation of neither the live nor neutral currents being centrally positioned (nor equally off centre) in the core, and the cancellation of the magnetic fields getting a few percent out of kilter - perhaps more of the flux from the neutral escaping through the gap in the jaws, or is the steel getting magnetically non uniform and needs de-gaussing.
How much current is the heater taking - i.e, what % imperfection in the cancellation are we talking about ?
Mike.
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