Service Disconnect

[Bill Ruffner]

Scenario: A commercial building has four individual 200A 120/240V single phase meters. Each meter will use either a separate 100A RT 120/240V disconnect or a separate 150A RT 120/240V disconnect.

Can you please tell me the manufacturer and catalog number of the 100A & 150A disconnect that you would use in this situation?

Thanks for your help.

 

[mcclary's electrical]

Scenario: A commercial building has four individual 200A 120/240V single phase meters. Each meter will use either a separate 100A RT 120/240V disconnect or a separate 150A RT 120/240V disconnect.

Can you please tell me the manufacturer and catalog number of the 100A & 150A disconnect that you would use in this situation?

Thanks for your help.

I just did a quick search, I've never used these, but it seems like a good price for the job.


http://www.homedepot.com/Electrical-Breakers-Distribution-Load-Centers-Load-Centers-Combo/h_d1/N-5yc1vZ1xr5Zbm1b/R-202046217/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

 

[Buck Parrish]

I would change the scenario and use a Siemens Meter base combo with discos. beside each meter. You can use a 100 , 150 or 200 amp breaker. Each meter is rated for the 200 amps.

Cutler Hammer's BR line is cheaper. If you could go with 125 amps each you would get out much cheaper.

 

[Bill Ruffner]

I just did a quick search, I've never used these, but it seems like a good price for the job.


http://www.homedepot.com/Electrical-Breakers-Distribution-Load-Centers-Load-Centers-Combo/h_d1/N-5yc1vZ1xr5Zbm1b/R-202046217/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

I agree with using the meter main combo but the scenario that I have to address uses a separate disconnect. However, thanks for taking the time to do the search for me. I appreciate it.

 

[Bill Ruffner]

I would change the scenario and use a Siemens Meter base combo with discos. beside each meter. You can use a 100 , 150 or 200 amp breaker. Each meter is rated for the 200 amps.

Cutler Hammer's BR line is cheaper. If you could go with 125 amps each you would get out much cheaper.

When you suggest a meter base combo, are you referring to a 4 socket meter bank?

 

[mcclary's electrical]

I agree with using the meter main combo but the scenario that I have to address uses a separate disconnect. However, thanks for taking the time to do the search for me. I appreciate it.

I read you question too quickly, if your leaving the meter bases in place, and just replacing disconnects, what I showed you won't work. But if you start from scratch, it will be a clean look. I don't use these much because I get free meter bases.

 

[Bill Ruffner]

I read you question too quickly, if your leaving the meter bases in place, and just replacing disconnects, what I showed you won't work. But if you start from scratch, it will be a clean look. I don't use these much because I get free meter bases.

I agree with you that meter main combos would be the better choice. I'm trying to find out what the common installation method is for this type of install. Following are the parameters that I have been given:

• 
  500 kcmil Feeders in 3" PVC run to an 8x8x120 wireway mounted on the exterior of the building

• 
  Four separate meter sockets will be mounted above the wireway

• 
  Each meter socket will have a separate RT disconnect

• 
  Each disconnect will feed an interior MLO panel.

One thing that I have learned is that installation methods differ from one part of the country to the other. I personally would use a meter main combo but I'm just some yahoo outside of Chicago so what do I know? I just need to find out what disconnects most people would use in this scenario.

This installation is not real. It is being used as an illustration in a book. I assumed that this must be a common installation method in other parts of the country. Maybe it's not. I'd be interested in hearing if anyone agrees with it.

 

[chris kennedy]

• 500 kcmil Feeders in 3" PVC run to an 8x8x120 wireway mounted on the exterior of the building

Sounds a little tight.

Bill, here I would use Siemens HF224NR.

 

[Bill Ruffner]

Sounds a little tight.

Bill, here I would use Siemens HF224NR.

I haven't taken the time to look but I'm assuming that the sizing is based on the minimum code requirement.

I was thinking of using a fused safety switch but I wanted to make sure that using a breaker disconnect wasn't a more common method.

Thanks Chris.

 

[Buck Parrish]

I agree with you that meter main combos would be the better choice. I'm trying to find out what the common installation method is for this type of install. Following are the parameters that I have been given:

• 
  500 kcmil Feeders in 3" PVC run to an 8x8x120 wireway mounted on the exterior of the building

• 
  Four separate meter sockets will be mounted above the wireway

• 
  Each meter socket will have a separate RT disconnect

• 
  Each disconnect will feed an interior MLO panel.

One thing that I have learned is that installation methods differ from one part of the country to the other. I personally would use a meter main combo but I'm just some yahoo outside of Chicago so what do I know? I just need to find out what disconnects most people would use in this scenario.

This installation is not real. It is being used as an illustration in a book. I assumed that this must be a common installation method in other parts of the country. Maybe it's not. I'd be interested in hearing if anyone agrees with it.

What you have described is very common here to in NC.
It is common in retail and industrial. It's a much more vesatile set up. 3 phase would be even better.

We would be required to use a 12x12 gutter not 8x8.
Your meters and disconnects can not be set back more then 6" of the face of the gutter above or below.
They should be okay if you use 11/2 strut on the meters and discos and none on the gutter.

 

[Alwayslearningelec]

Don't know if I should have posted a new thread for this.

What is a meter main combo. Is it just how it looks/sounds, the meter and your main sevice disco? When are these used most often?

Thanks.

 

[Bill Ruffner]

Thanks Buck. Would you use a fused safety switch or a breaker disconnect? If you would use a breaker disconnect, could you please provide a catalog number?

 

[chris kennedy]

The Siemens number would be W0406ML1225CU.

 

[Bill Ruffner]

Don't know if I should have posted a new thread for this.

What is a meter main combo. Is it just how it looks/sounds, the meter and your main service disco? When are these used most often?

Thanks.

A meter main is just as you thought. It contains a meter socket and a breaker disconnect in a single unit. They can include a single meter/disconnect or multiple meters/disconnects. They offer a quick and clean installation when a main disconnect is required. However, they can often cost more than a separate meter and separate disconnect arrangement. I guess it's a trade off between less labor/cleaner appearance and lower material cost.

 

[Bill Ruffner]

The Siemens number would be W0406ML1225CU.

So rather than using one that has a specific size main breaker factory installed, you just use the same circuit breaker enclosure and then add whatever size main breaker you need.

 

[augie47]

Since you are talking in generic terms, keep in mind the decision on fusible vs breaker mains can be affected by the AIC of the system.
Possibly not a consideration in this size arrangement, but locally, anything 400 amps or larger (or added to a service of that size) requires attention to the AIC and often times series rating with a fusible disconnect is less expensive than series rating with breakers.

This SqaureD brochure shows some of the fuse-breaker series rating listings.
http://static.schneider-electric.us...rvice-section-switchboards/2700DB9901R407.pdf

 

[chris kennedy]

So rather than using one that has a specific size main breaker factory installed, you just use the same circuit breaker enclosure and then add whatever size main breaker you need.

Breaker sold separately.

Here is a link to the Speedfax.

 

[Alwayslearningelec]

A meter main is just as you thought. It contains a meter socket and a breaker disconnect in a single unit. They can include a single meter/disconnect or multiple meters/disconnects. They offer a quick and clean installation when a main disconnect is required. However, they can often cost more than a separate meter and separate disconnect arrangement. I guess it's a trade off between less labor/cleaner appearance and lower material cost.

Thanks very much for that. I thought I saw a pic with a mter and several breakers. Is there such a unit? I know you mentioned unites with several meters and several discos but I am referring to only one meter but several discos. Does not seem to make sense but just making sure. Thanks