Old Equipment

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Electrical Designer
Mainly panelboards but also any distribution equipment. Does any standard exist or guidance on when equipment should be replaced if it’s too old? As a contractor, Is there a certain number of years or other indicators that would cause you the need to replace in order to warranty your work or just feel comfortable about it.

I have looked at ashrae guidelines for mechanical equipment just to get an idea. The state school commission has 30 year as a mark to replace equipment no matter what if they are involved in funding.
Does availability of compatible breakers come in to play?, We typically replace federal pacific equipment no matter what is there any manufactures or styles that are on a list of need replaced no matter what for you.

Thanks in advance for any input I wish there was something concrete to battle “unless it doesn’t meet code we don’t want to replace it”

My standpoint is from a designer in the office where field data is limited to what you can without a screwdriver in most cases, no opportunity for testing prior to the start of construction.
 
There is a difference between 20-year-old equipment and 50-year-old equipment and 100-year-old equipment. At some point the equipment probably should be replaced if there is work going on that makes it practical to do so.

I would not be replacing stuff based solely on age but if you decide to refurbish an area and there is some ancient equipment servicing that area it's probably a good idea to replace it as part of the refurbishment.

I don't know that you can make a general statement that after so many years you should replace stuff. A lot of electrical gear will last for a very long time but it does wear out and older gear may not function properly. Some of this is a judgment call which means the cheap amongst us will never replace anything that's still working, but that's the judgment call they're making.

A lot of this stuff can't be economically tested and I would say if you've got 50-year-old panel boards it would probably just be a good idea to replace them if you are doing a major remodeling of the area for whatever reason. But I also think if you are going to go to the trouble to replace panel boards it probably makes sense to replace all of the electrical.
 
There are some panels that have known reliability issues and the older they are the greater the risk of failure of the equipment. Some have history of failure to trip and that is definitely a saftey issue. Others have no ability for the newer safety devices such as GFCI. Another factor could be the panels AIC rating might be inadequate for current available fault current if there is significant age to the panel. With POCO changes and additions to the systems, that I've witnessed, had no recalculations made in the 50yrs from first installation leaving a potential for catastrophic failure.
Many times over the years unqualified persons will have altered without figuring in the new loads and creating an overload situation that was minimal enough that wouldn't trip the breaker but enough to cause a failure over time. All these can be argument for replacement but from code enforcement perspective some minimally so.
 
Appreciate all the responses. Very helpful and informative. I think the POCO changes is the closest I will get to a engineering argument when needed. Especially one of the recent ones I dealt with we anticipate the POCO possibly making some upgrades even though the new design doesn't warrant a change in service size. This one also has major gut and renovation of the entire building so everything seemed to push towards upgrading some equipment as well. Thanks again.
 
Fred B said:
Many times over the years unqualified persons will have altered without figuring in the new loads and creating an overload situation that was minimal enough that wouldn't trip the breaker but enough to cause a failure over time. All these can be argument for replacement but from code enforcement perspective some minimally so.
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As long as the breakers are sized correctly, I don't see how you would ever get into an overload situation. Worst case, a breaker trips. No safety issue. Just a nuisance.
 
petersonra said:
As long as the breakers are sized correctly, I don't see how you would ever get into an overload situation. Worst case, a breaker trips. No safety issue. Just a nuisance.
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But a breaker is generally not designed to hold over time a continuous load approaching or slightly exceeding the rating of the breaker. Ie., a 20 A breaker may hold for a long time at 21 or 22 amps but it will with an extended duration begin to damage the breaker. I've seen both where the breaker seizes and either will not trip on a full overload or trips but will not reset or as on a Pushmatic looks tripped but still allowing current to flow.
 
Fred B said:
But a breaker is generally not designed to hold over time a continuous load approaching or slightly exceeding the rating of the breaker. Ie., a 20 A breaker may hold for a long time at 21 or 22 amps but it will with an extended duration begin to damage the breaker. I've seen both where the breaker seizes and either will not trip on a full overload or trips but will not reset or as on a Pushmatic looks tripped but still allowing current to flow.
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It either trips or it doesn't. It can stay at full load or slightly above indefinitely and not harm the breaker.

Keep in mind how a breaker works. It is all about heat. The actual trip point is a function of the ambient temperature and the amount of heat generated by the thermal element in the breaker. If the ambient temperature is lower it will take more heat from the thermal element to trip. If the ambient temperature is higher, less heat from the thermal element is required to get a trip.
 
Fred B said:
But a breaker is generally not designed to hold over time a continuous load approaching or slightly exceeding the rating of the breaker. Ie., a 20 A breaker may hold for a long time at 21 or 22 amps but it will with an extended duration begin to damage the breaker. I've seen both where the breaker seizes and either will not trip on a full overload or trips but will not reset or as on a Pushmatic looks tripped but still allowing current to flow.
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Your scenario, IMHO, is only applicable when the contact resistance of the breaker contacts is so high that long term operation at or just above the nominal set point can cause slow thermal damage to the contact surfaces or burn out the internal lubricant of the mechanism.
Both of these circumstances are indicaitve of a design flaw in the breaker, not a normal expected behavior.
 
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