DC current through a domestic supply meter

These questions came up through some discussion on another technically/ scientifically unrelated news group ................... ?

1) What happens if a DC current** flows through a domestic/residence supply meter?

2) Would it be any different if the meter was the older 'spinning disc' type or the more modern 'digital' display type?

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1) Meter might register impulses of current in one direction only? Also since current flow would be only during a half cycle only half the energy would be transferred? AC motors would not work and anything with a transformer would output a weird waveform of half voltage or less?

2) Unknown?

PS. ** Hard to understand in what context the question was based! Gather that in fact the current 'might' be a 'mixture' of domestic AC and some DC (e.g. welding, without an interposing transformer ???). So that an AC current could have a DC bias in one direction or other????? All very puzzling!

Reply to
terryS
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It gets measured, and you pay for it. The pole-pig transformer that connects to your house always outputs zero DC voltage, but that doesn't stop your house's appliances from sucking more current on the positive side of the AC wave, i.e. DC current.

No. The display notwithstanding, both meter types do a true power measurement.

Reply to
whit3rd

The electromechanical "spinning disc" uses induction to produce eddy currents in the disc. I don't think it would spin at all with DC applied.

See

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Best regards, Bob Masta DAQARTA v5.00 Data AcQuisition And Real-Time Analysis

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Reply to
Bob Masta

"Bob Masta"

** Such use two inputs - voltage AND current.

No matter what load is applied, the voltage always remains AC.

I doubt the instrument will be out by much if someone uses a diode in series with the load.

...... Phil

Reply to
Phil Allison

some use eddy currents to drive the disc (like the one on wikipedia)

others use a motor to drive the disc and a permanent magnet to brake the disc. (voltage provides the field, current flows through the rotor)

Reply to
Jasen Betts

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