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Electronics => Projects, Designs, and Technical Stuff => Topic started by: Dreamer1 on August 21, 2013, 07:15:07 am

Title: Variable Frequency GFCI
Post by: Dreamer1 on August 21, 2013, 07:15:07 am

Does anyone have any experience with working with variable frequency GFCI chips? Maybe some documents?
from need to work from 20-600hz.

My google fu is strong failing me.

thanks!

Title: Re: Variable Frequency GFCI
Post by: johansen on August 21, 2013, 07:32:57 am

as far as i know they don't limit their bandwith.

meaning 400Hz at 120v, the 4NF Y cap will trip any common GFCI breaker, as that's 8mA of reactive current.

Title: Re: Variable Frequency GFCI
Post by: SeanB on August 21, 2013, 06:02:28 pm

They do not work on 400Hz, have seen them used on ground power installations so pressed trip to test it ( wanted so see if the secondary safety device was working to protect me) and it did not trip. Pulled it out of the board, connected to regular mains power and it tripped. Left a note that they do not work on 400Hz mains to warn the other users.

modern ones might do it, you will have to rip it apart and see which chipset they have used, some are specced for 400Hz, but if they are using an AC trip coil they might trigger but not trip, and you will have to modify them to get the coil to have a DC supply to trip it.