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Old 09-22-11, 09:41 AM   #18
Xringer
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Start up current on small asynchronous AC motors isn't a big deal,
because they don't develop instant foot pound of torque, like your power drill.
No big jump in current, and what jump there is, doesn't last very long..

Like, if you turned on your fluorescent lights and got a 10 amp surge for 1 hour,
that would be 120v x 10A, or 1.2kwh on your bill.
If the surge was for 1 second, that would be 0.333kwh on your bill..
If it was actually only for 0.1 of a second, that would be... 0.0333 kwh (.007 cents here)

Of course, the actual inrush current pulse might be shorter than 0.1 sec..

This power supply with a large filter cap draws a big inrush, but look how long it is.. 8ms?? That's 0.008 seconds!


Inrush Current
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