Is there any rule-of-thumb for older circuit breakers?
Should they function correctly indefinitely?
Does it depend on brand?
For replacement - replace entire panelboard when replacement circuit breakers are no longer available?
No rule of thumb, other than testing and finding problems, which is usually not practical for anything but large breakers (i.e. not residential stuff).Is there any rule-of-thumb for older circuit breakers?
Maybe, if by "function" all you mean is pass current and trip on over current. I routinely see breakers still in service that are from the 40s and 50s. But with extreme age comes the risk that when needed most, they don't hold together when they DO trip and become shrapnel. You won't know until after it happens.Should they function correctly indefinitely?
Only in that some brands were bad from the get-go, hence they no longer exist.Does it depend on brand?
I would. There are almost always people willing to sell old obsolete breakers, but unless you can get a certified test report saying they have been tested and function (not just cleaned and switched), it's a risk you have to weigh against the cost to swap out the entire panel. Breaker brokers will not go to the expense of testing and certifying anything small.For replacement - replace entire panelbodra when replacement circuit breakers are no longer available?
Testing equipment is expensive and the cost of a new panel and/or breakers (for residential applications) is worth the peace of mind that your house isn't going to burn down because a breaker failed.
Especially if you have old galvanized steel plumbing!
Often times those breakers aren't operated in years if ever unlike those residential load centers.Thanks for the replies.
I am mostly concerned with commercial panelboards with branch circuit breakers (mostly 20A-1P).
There is no Rule of Thumb and you will never see a manufacturer give an End of Useful Life Statement on things like this. What contributes to the answer of when to replace is it's exposure and how it is used. A typical circuit breaker that has been tested and evaluated should long outlast you and me...it is designed for the normal exposure it gets. However, when they are exposed to things outside of the norm then anythings life can be shorter than expected. That's why us Electricians get paid the BIG BUCKS...to field evaluate and make determinations based on real life exposure.Is there any rule-of-thumb for older circuit breakers?
Should they function correctly indefinitely?
Does it depend on brand?
For replacement - replace entire panelboard when replacement circuit breakers are no longer available?
Those to me would be the least of my concern unless again they are located in areas of elevated exposure that would warrant the concern over time. In a normal situation it is not something I would be concerned with in terms of their ability to function. However, thats just my take on it as I am sure others will disagree....and we all know I support buying more Electrical Equipment if you deem you need it:angel:Thanks for the replies.
I am mostly concerned with commercial panelboards with branch circuit breakers (mostly 20A-1P).
....and we all know I support buying more Electrical Equipment if you deem you need it:angel:
You see me post about , " Edison Base Fuses " .
Still the best OCP and I trust the fuses to last .
I will have Edison Base Fuses in my Cabin ... Third World .
Don