Maybe a reader or two can email this guy with advice.
----- Original Message -----
From: "TomVote" <TomVote@Hotmail.com>
Newsgroups: alt.engineering.electrical
Sent: Sunday, September 15, 2002 11:29 AM
Subject: Melted Wire Nuts
> This group seems to have a good sense of humor and tolerance for novices. I appreciate that.
> Have a problem with a cira 1970's 120v line (12-2g) running underground (40' tops) to a swimming pool pump. Had to replace the pump and decided to wire the outside switchbox to the pump with 12 guage instead of the 14 that was on it. Pump is 1hp 15 amp. Replacing the light switch (15a) that was in the box with a GFCI was a disaster, kept tripping the GFI, sometimes immediate and sometimes after the pump ran a few minutes. Decided to go without the GFI till I can get an electrican out to do everything right.
> So a pair of 12 guage being tough for an amateur (and weakling) like me to handle, I used large (red) wire nuts to make the direct connection in the box. Even went so far as to throw one on the groud wires to be sure they stayed connected. Shoved everything in the box and covered it with a metal blank face plate. Box is covered properly for outdoor use BTW, but I didn't check how I shoved the connectors in, sloppy.
> Pump ran for three or four days, then stopped. When I took the cover off the box, the wires were burned and the wire nuts were melted. Appears (can't be sure) that the ground came near, or in contact with the hot.
> Now the questions. The 20 amp circuit breaker never tripped. Shouldn't it have, with enough current flowing to generate the heat to melt the wire nuts? Redid it yesterday with medium (yellow) wire nuts, which I originally ignored because they looked to small. Packages for both large and medium list two 12 guage as acceptable. Any difference between using large or medium in this type of application?
> Thanks for any insights you can provide.
> Tom
[This message has been edited by Bjarney (edited 09-15-2002).]