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A wee bit of leakage

lyledunn

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. 

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    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.

Reply
  • 0

    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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