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Nick Ostrowski
05-13-2008, 07:15 AM
Does anybody have an idea how long it has been required for service panels to need no more than 6 throws of the hand to denergize the entire panel? I saw an older split bus panel yesterday that needed 10 throws to shut it down.

Matt Fellman
05-13-2008, 07:27 AM
I don't think there was ever a time 10 was okay. All I've ever heard was 6 and now 1. I suppose it's possible that there was a time period that it just wasn't addressed so you could find anything.

But really, circuit breakers didn't come about until the 50's/60's and by the 60's I'm pretty sure it was the 6 throws of the hand rule. I seem to remember even the old Pushmatic panels from the 50's/60's had a 'sub-main' and fell under the 6 switches.

Jerry Peck
05-13-2008, 09:14 AM
Does anybody have an idea how long it has been required for service panels to need no more than 6 throws of the hand to denergize the entire panel? I saw an older split bus panel yesterday that needed 10 throws to shut it down.

Back before time began ... :)

If there were more than 6 in the section which serves as the main (and which controls the other section), then it was improperly done, with improper breakers (the label will show a schematic showing the double pole breakers in the 'main' section, and it probably will not show any single pole breaker in that section - because that would allow the total number of 'mains' to exceed 6).

Richard Abrams
05-13-2008, 12:00 PM
6 disconnects is still the rule However these need to be grouped together and labeled. I have been in business since 1977 and there was never 10 disconnects allowed. Also becareful if it is a split bus panel as there are little different.:)

Nick Ostrowski
05-13-2008, 10:01 PM
Thanks guys.