Fused Neutral

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sfav8r

Senior Member
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San Francisco Bay Area
I was on a service call today and found a panel with fused neutrals (pretty common here with all the old homes).

Normally, we can attach the neutrals in such a way that they are no longer fused. This particular panel design prevents that.

Any suggestions on the best way to bypass the fused neutrals? I think the cleanest method would be to install a neutral bar, but it seems that would not be kosher as it is a field mod. to the cabinet.

The hot side has all been converted to type "S" to prevent over fusing. The client was willing to put in a new panel, but unfortunately here in SF, if you are upgrading the panel, they require you to move it out of the closet which in this case is a MAJOR project that the customer can't afford right now.

Sorry I don't have a pic to show this better, but I didn';t have my camera today.

Thanks for any input.
 
Re: Fused Neutral

Originally posted by georgestolz:
How big are the wires? I'd imagine you could use a blue wire nut?
Click to expand...
They are only #12 & 14, however there are 18 circuits and most of the wires have very little play in them. I'm not sure it would be possible to route them all to a single location.
 
Re: Fused Neutral

There is such a thing as a dummy fuse for this situation. Dummy fuses are also used in corner grounded 3-phase systems where it is desired to disconnect the grounded conductor with the hot wires. In a corner grounded system the grounded conductor is NOT a neutral.
 
Re: Fused Neutral

A dummy fuse would be exactly what the doctor ordered. I was assuming they didn't make such a beast because as soon as someone screwed one into their kitchen circuit and burned the house down the manufacturer would get sued.

I emailed bussman to see if they make one (couldn't find it on their site).

Thanks

[ March 23, 2005, 02:52 PM: Message edited by: sfav8r ]
 
Re: Fused Neutral

I found them under Cooper Bussmann part number ENA(Edison Neutral Adapter) :confused:

Couldn't find them locally, but our supplier was able to order with a 1 week lead.

Thanks again.
 
Re: Fused Neutral

Back in the 1980s somebody was making a dummy cartridge fuse. I think it was Bussmann. You had a hard time getting these any place outside of say Boston, MA or NYC where neutral fusing was once done.

BTW, in corner grounded motor circuits the branch circuit protection is also supposed to have a fuse or circuit breaker pole so as to protect the one overload relay from short circuit return current. This is the only place where a fuse is still allowed in a grounded conductor. In a corner grounded system blowing a fuse in the grounded conductor only causes a single phase condition.
 
Re: Fused Neutral

Oops, at 3:45 a.m. I forgot to insert that on corner grounded motor circuits the brand circuit protection is supposed to have a fuse or circuit breaker pole in the grounded conductor. See above for why.
 
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