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Posted By: jbfan control transformer - 02/16/04 10:03 PM
Do I need to bond the neutral of a 208v to 120v control transformer. The panel that feeds the transformer has the ground and neutral bonded inside the panel. It is a 500va transformer.

Posted By: golf junkie Re: control transformer - 02/16/04 10:30 PM
No, You can bond it or let it float at your option. I prefer to bond makes voltage reading to ground more meaningful, makes troubleshooting easier.


[This message has been edited by golf junkie (edited 02-16-2004).]
Posted By: Bjarney Re: control transformer - 02/16/04 11:53 PM
Please consider grounding the 120V-secondary winding. For 1000VA-and-under control-power transformers, NEC 250-30 allows the winding to be grounded with a simple 'case' jumper. The usual full-tilt grounding-electrode/building-steel connection is not needed. This is a real easy way to keep electrostatically-induced garbage off the control circuit.

[This message has been edited by Bjarney (edited 02-16-2004).]
Posted By: jbfan Re: control transformer - 02/17/04 12:53 AM
Thanks for the answers. It will be bonded tomorrow!
Posted By: Scott35 Re: control transformer - 02/17/04 02:19 AM
I second Bjarney's suggestion!

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