Was sent on service call, some outlets weren't working. Spent hours crawling over and under this large house, that had been converted into several apartments, trying to trace the circuit.
What I had faild to notice in my first examination of the fuses at the service panels was that this disconnect (for one of the water heaters) had had a lampholder added to its' side. (Old keyless lampholders did not have the largebases they have today). Sure enough- the lampholder was being used as a fuseholder- and some passers-by had stolen the fuse.
[This message has been edited by Webmaster (edited 04-25-2005).]
I came across this in answer to a similar question
According to Section 410.47, “Lampholders of the screw-shell type shall be installed for use as lampholders only.” Section 240.50(B) requires fuseholders for plug fuses to be marked with ampere ratings.
Looks like you would have to examine the device to see if it was a lampholder or a fuseholder.
Thanks, MX! I do note that the second item is described as "660 watts," which kind of limits its' use as a fuse holder.
I am quite sure that a given item, when presented to UL, will be tested to different standards, depending on whether it is described as a "luminaire" or a "fuseholder."
I will also concede that there are robust lampholders, and rather (shockingly) flimsy fuseholders.
I am not as enthusiastic in my condemnation of this practice (using a lamp holder as a fuse holder) as some are- but there are limits to the "field endineering" that is appropriate.
Just because the fuse fits doesn't make it right. One would hope to find branch circuit fuses in the fuse box, not tacked on to a remote disconnect. (BTW, the fuse holder was in no way associated with what the disconnect served). The holder, and fuse, are exposed to the weather. With the fuse removed, you had a live point directly exposed to passersby.
I suppose that, were one to mount such a fuse in a panel, controlling a circuit associated with the panel, I wouldn't think twice about it.
To borrow a phrase from TV: "Don't try this at home!" :-)