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Jim McMillan
11-27-2012, 04:29 PM
I often don't have reference documents for construction requirements older than mid-1990's. I recently called out an 1972 service equipment panel for having nine disconnects. I do not know when the code was put in effect that required no more than six cut-offs to terminate all power. Repair person (contractor) doing the repairs on this house says this panel is grandfathered in and no changes need be made. Can anyone enlighten me as to whether he is correct for this year construction, or am I?

Jerry Peck
11-27-2012, 05:40 PM
Basically, from Day One of the NEC, the requirement was for one disconnect when it was mentioned, then an exception came in to allow 6 for residential dwellings - thus the opposite of what that person was saying is true ... only one was allowed ... until the exception for 6 came in, and that was, as I recall, sometime in the 1920s or 1930s ( I looked it up once, you may be able to find it here in a search).

Lon Henderson
11-27-2012, 06:15 PM
Thanks Jerry, I have been asked about this too, and have replied that the "no more than 6 throws" goes back further than anybody's memory (that I knew). But, I never actually knew more than that.

Garry Blankenship
11-29-2012, 12:40 PM
The six disconnect rule came on an etched stone tablet carried here by The Mayflower. You would have to do some real research to find the legal origin of the six disconnect rule, but I doubt any granfather laws would help any existing electrical service with being allowed more than six disconnects. Somebody has a good line of bull.

Jerry Peck
11-29-2012, 05:56 PM
The six disconnect rule came on an etched stone tablet carried here by The Mayflower. You would have to do some real research to find the legal origin of the six disconnect rule, but I doubt any granfather laws would help any existing electrical service with being allowed more than six disconnects. Somebody has a good line of bull.

Garry,

Quite incorrect. Yes, I know you were exaggerating, and it just 'seems like it was on the back side of the stone tablets Moses held' ... but still, let's keep it more accurate, especially after more correct information was already posted.

I researched it back through my NEC codes and the six disconnect exception came in long after the first NEC, and that six disconnect exception was strictly for residential work for some time. The exception changed over time to include other than residential.


Basically, from Day One of the NEC, the requirement was for one disconnect when it was mentioned, then an exception came in to allow 6 for residential dwellings - thus the opposite of what that person was saying is true ... only one was allowed ... until the exception for 6 came in, and that was, as I recall, sometime in the 1920s or 1930s ( I looked it up once, you may be able to find it here in a search).

At some point in time when I have nothing by time on my hands I will need to go through my old codes and create a list of what happened when ... someday ...

Alton Darty
11-29-2012, 07:46 PM
1959 NEC 230-70(g) contains the requirement that the disconnecting means be accomplished by no more than six operations of the hand.
Sorry but this is the oldest version of the NEC that I have on my desk right now. I may try to dig out some of the 20's or 30's versions that are that are somewhere in my office, but I am also sure that the requirement exists in editions earlier than those.

Michael Chambers
11-29-2012, 11:39 PM
It seems to me that the really pertinent question is was there ever a time when more than six throws were allowed? It doesn't sound like that that was ever the case.

I'd throw that at the electrician, then ask him to put it into writing on his signed letterhead that there is nothing wrong with this installation. Why would an electrician argue against getting to do a paid repair, unless he's the one who did it wrong in the first place.

Jerry Weaver
11-30-2012, 01:11 PM
Hi all.
Jerry Weaver , Elite Home Inspections, Portland, Or here. Retired and loving it!

Anyway, even the typical fused panel only had 6 disconnects. 1 main, 1 range and 4 replaceable fuses. That is what I would tell anyone who questioned my calling out more than 6 throws. It has been 6 max beyond my lifetime!

Garry Blankenship
11-30-2012, 05:14 PM
Garry,

Quite incorrect. Yes, I know you were exaggerating, and it just 'seems like it was on the back side of the stone tablets Moses held' ... but still, let's keep it more accurate, especially after more correct information was already posted.

I researched it back through my NEC codes and the six disconnect exception came in long after the first NEC, and that six disconnect exception was strictly for residential work for some time. The exception changed over time to include other than residential.



At some point in time when I have nothing by time on my hands I will need to go through my old codes and create a list of what happened when ... someday ...

Yes on the exaggerating; no on the quite incorrect. The OP indicated that he was given a "Grandfathered" reason for nine disconnects. The rule I worked under many years was 6 or less. I never researched historical code, but even when demoing out very old buildings w/ handled knife switch mains, fuses and coppers buss bars there were never more than one, ( admittedly commercial work ). What I said about finding a service where nine disconnects were once legal is not going to happen I still consider true until someone can show me something to the contrary. Until you can prove it incorrect other than by a J.P. pronouncement, it remains correct. BTW; the OP stipulates a 1972 service installation.