[Shop-talk] Replacing a breaker?

[Wayne]

On 4/7/2011 12:41 PM, Scott Hall wrote:
> Now...before I just Google "how to replace a breaker" and do that, I
> thought prudence dictated I ask someone smarter than me (that's you guys
> :-) ).

Well, the "correct" answer is "hire an electrician" or "shut off the box 
main to the whole house and replace it."  Swapping or adding a breaker 
on a live panel is standard practice though -- at least for licensed 
pros.  What they do is flip off the breaker;  each one hinges in at the 
center of the panel (at least on every modern panel I've seen worked 
on); pull at the outboard edge to swing it out; unscrew hot lead; 
reconnect to new breaker with it TURNED OFF; insert into center hinge; 
snap down into outer power rail; switch on.

Disclaimer:  Any amateur foolish enough to attempt this possibly lethal 
task should probably at least try it on a dead panel first.  Note -- 
even if you switch off the main, the leads in from the meter and the big 
terminals are still hot.  And the ground and neutral bus are only 
non-hot in theory.

Even though almost all brands of breakers and panels are mechanically 
interchangeable, you have to match brands and products to be NEC compliant.

-w