OPEN BREAKERS REMOTELY ?

[hawkeye23]

I am trying to come up with a means to open 400-600 amp molded breakers remotely in a emergency .
These breakers are already installed for 15years or so. The only way I know to do this is with shut trip breakers , this would mean we would have to replace many breakers.
Any help with this idea would be appreciated .

 

[GoldDigger]

I am trying to come up with a means to open 400-600 amp molded breakers remotely in a emergency .
These breakers are already installed for 15years or so. The only way I know to do this is with shut trip breakers , this would mean we would have to replace many breakers.
Any help with this idea would be appreciated .

There are remote lever actuators available for any breakers that can be operated manually. In most cases they would be attached to a CB that needed to be deliberately operated while energized with a high risk of an Arc Flash incident. But they can also be left in place. You would need to see how expensive they would be compared to replacing the breakers with shunt trip models.
For a small breaker, replacement would be cheaper if you can find one to fit the same space.

I have not looked to check what is available specifically for molded case breakers, but it is worth a network search. Or other members may have some specific suggestions.

How many breakers do you have to protect this way?
Would this be remote manual override by an operator, or do you need it to be automatic from some sort of control or protective system?
Do you have to open individual breakers rather than cutting off a whole panel or feeder?

 

[weressl]

There are remote lever actuators available for any breakers that can be operated manually. In most cases they would be attached to a CB that needed to be deliberately operated while energized with a high risk of an Arc Flash incident. But they can also be left in place. You would need to see how expensive they would be compared to replacing the breakers with shunt trip models.
For a small breaker, replacement would be cheaper if you can find one to fit the same space.

I have not looked to check what is available specifically for molded case breakers, but it is worth a network search. Or other members may have some specific suggestions.

How many breakers do you have to protect this way?
Would this be remote manual override by an operator, or do you need it to be automatic from some sort of control or protective system?
Do you have to open individual breakers rather than cutting off a whole panel or feeder?

Shunt rip CAN be added to existing breakers. Motor operator is more expensive way to go.

 

[templdl]

Shunt rip CAN be added to existing breakers. Motor operator is more expensive way to go.

Yes but if the breaker is sealed by breaking the seal to remove the cover to add an accessory such as a shunt trip would be in violation of the UL listing. If the breaker is marked with Line and load it is most likely a sealed breaker.
But, a breaker of that size is probably not sealed where you are able to purchase a shunt trip and install it in the field
In order to do so all power must be removed from the breaker first before there is any attempt to remove the cover. You must also have a source of power to activate the shunt trip which is commonly 120vac and a means of activating it such as a N/O momentary switch. Other voltages can also be used such as 24vac. I doesn't have to be momentary because the shunt trip itself has a cut off switch but a N/O contact switch would be better.
As pointed out a motor operator that can be attached over the front of the breaker is another option. Motor operators have the ability to operate the actual toggle itself giving you the ability to not only turn the breaker off remotely but also turn it Bach on. Motor operators are not as fast as a ST because the ST actually opens the breaker by hitting the trip bar.
When you trip the breler with the ST you my latch (reset) the breaker before the toggle can be moved back to the closed position.

 

[Jraef]

Shunt rip CAN be added to existing breakers. Motor operator is more expensive way to go.

I agree, in fact many times, motor operators will cost more than new breakers.

15 years old is not exactly ancient (at least I like to think so). By then many breaker mfrs had already started shipping their breakers with "accessory pockets" that are on the front of the breaker housing. You can install a shunt trip (or any other accessory) in the field by simply removing the pocket cover, placing the ST module inside, running the wires out of a provided slot, and reinstalling the cover.

Even if you have the older type where the breaker had to be removed and disassembled to install the ST from the back, violating the UL label is kind of a moot point on equipment already installed and in use. Once it's yours, installed, inspected and approved, it's yours. But in reality, it's not an easy task. If I had older breakers like that, I personally would contact the breaker mfr and see if their more up-tp-date version with the pockets is available to retrofit without adaptation and just do it that way. Less hassle, less field time, less risk of doing something wrong. Granted, 400-600A breakers aren't cheap, but neither is my time.

Trick of the trade: if you need several, don't buy loose breakers. Buy a panelboard interior with the breakers you need in it, with bus bar as small and cheap as they will let you buy, no cover, no box if they will allow it (some wont) then throw out the interior and all the superfluous crap to just use the breakers. Unless you are a high volume OEM, assembled panelboards are generally sold MUCH cheaper than replacement loose breakers.

 

[templdl]

Trick of the trade: if you need several, don't buy loose breakers. Buy a panelboard interior with the breakers you need in it, with bus bar as small and cheap as they will let you buy, no cover, no box if they will allow it (some wont) then throw out the interior and all the superfluous crap to just use the breakers. Unless you are a high volume OEM, assembled panelboards are generally sold MUCH cheaper than replacement loose breakers.

Bingo, you picked up on that. I did this for a good customer when they winced at the cost of adding 2 480v air circuit breakers to a lineup that they were assembling. Since they were an OEM they had the benefit of purchasing a complete structure with the breakers for less than the breakers separately and just scrap the structure.The same thing should be consider with load center breakers to consider the cost of a load center filler with breakers verses the cost of the breakers by themselves.
And when I replied I had given some thought about the breakers with pockets but chose not to.
As for breaking the factory seal that most likely would be a mute point but would be of a concern of the NEC and if the AHJ would turn a blind eye. Basically you can do what ever you want if you can get away with it.

 

[weressl]

Bingo, you picked up on that. I did this for a good customer when they winced at the cost of adding 2 480v air circuit breakers to a lineup that they were assembling. Since they were an OEM they had the benefit of purchasing a complete structure with the breakers for less than the breakers separately and just scrap the structure.The same thing should be consider with load center breakers to consider the cost of a load center filler with breakers verses the cost of the breakers by themselves.

...and MCC's.