755 volt circuit breaker IEC requirements

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d-decherd

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To all, I have an industrial installation that requires a 755 volt rated breaker, 1600 amps, 25 kA SCI.
UL, CSA & IEC molded case breakers are all rated below this voltage.

Schneider Electric makes a IEC rated breaker that meets the system requirements.
The machine's manufacturer recommended the particular breaker. (NW16H10). The breaker will be installed separately from the existing machine.

1. Does IEC test molded case breakers or only set the standards to build the breakers?
2. This breaker model has not been tested by UL or CSA, therefore it is not listed or labeled by either agency.
3. By the NEC the electrical products are to be listed or labeled in order to be installed.
This product is neither listed or labeled so it looks like I cannot use it.
4. Does IEC list or label products, if they do is it acceptable in the U.S.?
5. Is there a list somewhere of IEC labeled or listed products?
 
The basic answer is that unless it is also rated as a UL489 breaker, the short circuit rating is meaningless.

IEC is a standards organization and does no testing or listing.

Most IEC breakers are rated at 690V anyway. 755V is a really odd voltage.

The NEC does not require that all electrical devices be listed, only those that are specifically required to be listed have to be listed. Some states and localities are more stringent.

I think I would be inclined to use a medium voltage CB of some sort. You will have to get an odd transformer anyway.
 
755 volt circuit breaker IEC requirements

This is an existing system being modified to mitigate arc flash. Thanks for the AIC rating update. The manufacturer lists the SCI as 50ka.
 
d-decherd said:
This is an existing system being modified to mitigate arc flash. Thanks for the AIC rating update. The manufacturer lists the SCI as 50ka.
Click to expand...

Is that rating at 755V though?

This is a curious situation. Maybe you could give us more information on just what you are doing to satisfy my curiousity.
 
755 volt existing machine modification

755 volt existing machine modification

We are trying to reduce the arc flash at the main breaker on the machine from dangerous to level 2.
The 755 volt transformer is existing. The main circuit breaker on the machine is operated by technicians to shut off the unit. There is no secondary breaker at the transformer. We are planning on adding a remote operated, trip and close breaker at the transformer to reduce the arc flash. I need a circuit breaker and outdoor housing that will work with the ratings of 755 volts and 1600 amp frame.

I will look at the mining breaker today and get opinions here.
This is an option I had not thought of, thanks.
 
d-decherd said:
We are trying to reduce the arc flash at the main breaker on the machine from dangerous to level 2.
The 755 volt transformer is existing. The main circuit breaker on the machine is operated by technicians to shut off the unit. There is no secondary breaker at the transformer. We are planning on adding a remote operated, trip and close breaker at the transformer to reduce the arc flash. I need a circuit breaker and outdoor housing that will work with the ratings of 755 volts and 1600 amp frame.

I will look at the mining breaker today and get opinions here.
This is an option I had not thought of, thanks.
Click to expand...

Why not just get a remote operator for the existing breaker? Easier, cheaper, and no downtime needed to install.
 
755 volt existing machine modification

755 volt existing machine modification

The existing breaker is inside of the manufacturer's machine. Having the manufacturer modify the breaker will take at least a year. We need a more immediate solution. The customer does not want to modify this "Proprietary equipment". It is easier to work on the feeder going to the unit. The existing molded case breaker has a built in Under voltage trip that has to be manually reset in order to close the breaker. The electrician is standing in front of the device when operating the breaker.
 
d-decherd said:
The existing breaker is inside of the manufacturer's machine. Having the manufacturer modify the breaker will take at least a year. We need a more immediate solution. The customer does not want to modify this "Proprietary equipment". It is easier to work on the feeder going to the unit. The existing molded case breaker has a built in Under voltage trip that has to be manually reset in order to close the breaker. The electrician is standing in front of the device when operating the breaker.
Click to expand...

You don't have to modify anything, there are remote operators on the market that attach to any breaker (Including molded case) and you can use a wirless remote to open and close it.
 
755 volt existing machine modification

755 volt existing machine modification

I am aware of the chicken switch remote operator.
Who are the other manufacturers?
 
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