FW500 Ground/Bond Issue

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FW500 Ground/Bond Issue

Postby JCO on Sun Jul 03, 2011 2:57 pm

Greetings.
I have just been testing the 48V AirX turbine wired into my FW500 box and found that it was energizing the entire box (bad buzz!). It is wired through the appropriate switch and breaker on the positive side, and wired directly to the negative buss. After removing the supplied bonding wire between the negative buss and the ground buss, there is still residual voltage, albeit at a very low rate. Two questions for the furoum:
1) Is this common for the FW500?
2) Why is the DC box shipped with the bonding wire between the negative and ground busses?

Cheers;
JCO
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Re: FW500 Ground/Bond Issue

Postby Kent Osterberg on Sun Jul 03, 2011 5:18 pm

1) No, this isn't normal. You should not get a buzz when touching the Flexware 500 panel.
2) A negative to ground connection is generally required to provide a low resistance path to ground so that ground faults will trip the dc breakers.

From your description, it sounds like there may be dc current flowing through the ground electrode(s). What kind of ground electrode is the Flexware 500 connected to? Is there a ground electrode at the wind generator? Do you have a ground wire running from the Flexware 500 to the wind generator?

Is there any chance that the buzz disappears when you turn the inverters off? If so, there may be a grounding problem on the ac side of the system.
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Re: FW500 Ground/Bond Issue

Postby tallgirl on Mon Jul 04, 2011 4:02 pm

This almost sounds like the wiring from the AirX is reversed. Any chance that's the case?
Julie in Texas

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