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Michael A. Terrell Michael A. Terrell is offline
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Default Cooling the shop.


Bob Engelhardt wrote:

Michael A. Terrell wrote:
Bob Engelhardt wrote:

...
When the
circuit is opened, the charge at that moment stays there.


Why? That would make the item dangerous to service. Maybe fatal.


"Why?" Because it's the physics. The physics doesn't care if it's
dangerous.

I've worked on equipment that had a 'Shorting Stick' along with HV
interlocks, in case the high resistance bleeder resistors failed. ...


These aren't storage capacitors, they are used to give a phase
shift. ...


They don't function as storage capacitors, but they can store charge.
Why are there bleeders and back-up shorting sticks? - because the
circuit can open with charge/voltage on the cap.

If they didn't have the built in bleeders, there would be a lot of
injured or dead HVAC types.


My comments have been more conceptual, my not being very familiar with
motor cap technology. I have never said that there weren't bleeders,
only that the motor could stop with a charge on the cap.

I have a collection of motor caps in my parts box. I randomly picked 6
and charged them to 100v. After 1-1/2 hours, 2 of them still had
significant charge: 1 97v & the other 99.



Then you shouldn't play with them till you learn how to do it
safely. Not all can capacitors are motor capacitors. Some are used as
filter capacitors, or coupling capacitors. You didn't put a bleeder
across them to make it a fair test, as well.