grouping of motor starters

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Crosstown

New User
Location
indiana
Occupation
electrician
Good evening, new to the forum. I have a question about grouping of motor starters. I was trained that if we have several motor starters, we could mount them in one enclosure and feed each individual motor starter from its own breaker that was located beside the panel where the motor starters are mounted. This is not a industrial site (mostly ag). I know that this wouldn't pass panel certification, but is there anything against this in the code book?
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
if opening the door to the stater panel obstructs the view of the breaker from the stater location, I could see an issue with 430.102(A) that requires the starter disconnect to be within sight from the starter.
 

kwired

Electron manager
Location
NE Nebraska
Good evening, new to the forum. I have a question about grouping of motor starters. I was trained that if we have several motor starters, we could mount them in one enclosure and feed each individual motor starter from its own breaker that was located beside the panel where the motor starters are mounted. This is not a industrial site (mostly ag). I know that this wouldn't pass panel certification, but is there anything against this in the code book?
It doesn't need to meet panel certification if it otherwise meets NEC requirements.

That said, something to at least consider is NFPA 70E. I don't know 70E real well myself, but the trend seems to be going to you don't open an enclosure with live components (other than power limited controls maybe), so if that is the case you need to turn off all the motor circuits feeding that enclosure to work in it if following those rules.

That said, done exactly what you described many times in the past, but it is NEC compliant - so far.
 

Russs57

Senior Member
Location
Miami, Florida, USA
Occupation
Maintenance Engineer
I think you are going to do better with one breaker, or disconect, mounted in the enclosure with external handle.......feeding power distribution block.....feeding individual fuses for each starter.

Otherwise, just put each starter in its own enclosure.
 

tom baker

First Chief Moderator
Staff member
In WA if you are installing a panel like you describe it probably would have to be UL508A listed. Better off to have a panel shop build it, they buy the parts cheaper than you do and you will have drawings.
 

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
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Electrical Engineer
All of the equipment mfrs make stand alone enclosed non-combination starters (meaning no breaker or disconnect with it), they are all UL listed on their own, they can all be installed on their own with an enclosed breaker or disconnect next to it or even in another room. There is noting prohibiting any of that in the NEC. "Starters lined up on the wall" was the norm for a long time in a lot of industries.

old rusted starters.jpg

There ARE however safety concerns with that and as kwired said, the advent of NFPA 70E and OSHAs requirement that all employers have an electrical safety program that emulates 70E at the very least, makes having separate parts like that more problematic than it used to be. In addition to that, the requirement for things to have an SCCR equal to or greater than the Available Fault Current is also a challenge for that scenario now too. The OL relays of motor starters are usually not listed for more than 5kA SCCR by themselves, but when you buy them as a listed combination starter, they are series listed with the breaker that comes with them for much higher values, often 65kA. So hooking up a loose starter and making sure there is no more than 5kA AFC at the terminals is possible, but not likely in an industrial setting and a lot of effort just to save next to no money compared to just doing it right. I've made comparisons for mounting a connecting a separate fused disconnect + a separate motor starter, including conduit to connect them, and the added labor alone makes it more expensive than just using a combo starter.
 

kwired

Electron manager
Location
NE Nebraska
All of the equipment mfrs make stand alone enclosed non-combination starters (meaning no breaker or disconnect with it), they are all UL listed on their own, they can all be installed on their own with an enclosed breaker or disconnect next to it or even in another room. There is noting prohibiting any of that in the NEC. "Starters lined up on the wall" was the norm for a long time in a lot of industries.

View attachment 2554392

There ARE however safety concerns with that and as kwired said, the advent of NFPA 70E and OSHAs requirement that all employers have an electrical safety program that emulates 70E at the very least, makes having separate parts like that more problematic than it used to be. In addition to that, the requirement for things to have an SCCR equal to or greater than the Available Fault Current is also a challenge for that scenario now too. The OL relays of motor starters are usually not listed for more than 5kA SCCR by themselves, but when you buy them as a listed combination starter, they are series listed with the breaker that comes with them for much higher values, often 65kA. So hooking up a loose starter and making sure there is no more than 5kA AFC at the terminals is possible, but not likely in an industrial setting and a lot of effort just to save next to no money compared to just doing it right. I've made comparisons for mounting a connecting a separate fused disconnect + a separate motor starter, including conduit to connect them, and the added labor alone makes it more expensive than just using a combo starter.
They also make them in 4x and 12x versions;)
 
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