From: clewis@ferret.ocunix.on.ca (Chris Lewis)
Newsgroups: misc.consumers.house
Subject: Re: Breakers vs fuses.
Date: 23 Dec 92 04:34:06 GMT
Distribution: na
Organization: Elegant Communications Inc., Ottawa, Canada

In article <1992Dec22.041238.11541@porthos.cc.bellcore.com> patter@dasher.cc.bellcore.com (patterson,george r) writes:
|In article <7214@atlas.cs.nps.navy.mil> erickson@atlas.cs.nps.navy.mil (David Erickson) writes:
|>In article <1992Dec18.192917.18401@bcars6a8.bnr.ca> clewis@ferret.ocunix.on.ca (Chris Lewis) writes:

|>>	- if it did, you're fuse box is in gross violation of the electrical
|>>	  code (being able to disconnect one side of 220V without getting the
|>>	  other).  These rules have been around at least 20 years....

|>Come on, now, Chris.  Most houses built since the mid-fifties (at least)
|>have had circuit breakers, not fuses.  Houses with fuses have electrical
|>systems that are at least 40 years old, perhaps much older.

|I wired a house myself to Tennessee code in 1969 and put in a fuse box for
|the main circuit protection. The Knoxville Utility Board made the approval.
|I wired another to South Carolina code in 1970 with a fuse box. In that
|case, Duke power company made the approval. This fits right in with Chris'
|20 years.

My first full house wiring job was in 1971 or 1972.  Fuse panels were still
by far the most common.  Somewhere around 1974 breaker panels became
very common, and shortly afterward became mandatory.

|> Therefore,
|>your conclusion is faulty, since the electrical code almost invariably
|>grandfathers in installations that were correct at the time they were
|>made.  The only way the fuse box would be in gross violation of the
|>code would be if it had been so at the time it was installed.

|If you take Chris at his word ("fuse"), you're correct. Any 220 line
|protected by two fuses can be left live when one of the two is removed.
|High amperage 220 lines, like stove lines, were typically protected with
|cartridge fuses located in a separate load box with a manual disconnect,
|but small ones like a dryer line used regular fuses in the main box. One
|could quite legally set up this dangerous situation.

Not so fast... ;-) in the 1970s our code required that all 220V lines had
ganged fuses - stoves/dryers with cartridge fuses, lower amperage with
ordinary screw-type fuses in a pull block that had to be
removed before the fuses themselves could be unscrewed.  Can't remember
who made the panel.  Rule probably went back to the mid 1960s.

The other thing to consider is, even if the panel itself was considerably
older than the 1970s, the line for the dishwasher couldn't date much
earlier than 1970 (residential dishwashers weren't around in the 1950s),
and that code at the time of installation would have to be followed.  By
our code, if the panel couldn't accept ganged pull-blocks, the dishwasher
would have to go thru a separate minipanel with a cartridge block.

What I really think happened with the original poster is that the first
fuse that he pulled wasn't connected to the dishwasher at all, and the
dishwasher was only 110V, and connected to one fuse, not two.
God knows I've encountered enough mislabeled panels, or worse, two
separate circuits going thru the same box...
-- 
Chris Lewis; clewis@ferret.ocunix.on.ca; Phone: Canada 613 832-0541
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