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Author Topic: How, specifically, does an electric meter measure wattage?  (Read 3369 times)
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Of course it's possible, but how and how safe it is may be a problem.  What kind of power meter is it?  What is the supply input to it.  This usually runs in big numbers: 50A, 100A, 200A?

If it's any of those numbers, you have a big problem outrunning it without blowing something up.  Not only would you have to use extremely large wire (or run the risk of the magic smoke escaping) and some pretty sophisticated protective clothing.  You're going to be channeling huge quantities of energy that can easily vaporize a few inches of copper, starting fires in insulation rated for 400C.

Sucking it faster than the meter can sense is not a good idea.
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Sucking it faster than the meter can sense is not a good idea.

I've seen a video of that being done, and by the time you are putting in enough current to stop the meter from registering you need extremely heavy cables on either side and a supply good for tens of thousands of Amps - and the meter quickly collapses into a pile of molten slag. This is obviously highly dangerous as well as being contrary to the spirit of the assignment.
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It's trivial to get a small bit of power without it being measured as mentioned above.  Impossible to get a large amount because of the rules you have defined.  So charge a Cap slowly, then power the light for 2 seconds.
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Would inductive coupling be detected by the meter?

« Last Edit: January 11, 2013, 12:01:35 pm by David82 » Logged

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Would inductive coupling be detected by the meter?


Yes. The magnetic field you're taking in the secondary has to be replaced by the primary, using current. If inductive coupling didn't take any power then no transformer would take any power either.
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