Best way to wire up four 1/2hp 3 phase fans

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dftmaint

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Each fans fla is listed as 2.2amp @ 208v three phase. They will be spread out like a clock at 12, 3, 6, and 9 o'clock. Distance from 12&6 and 3&9 will be 40 ft. I would hate to use 4 breakers for a combined total 8.8 amp. I though about manual toggle type starters from a central junction box. One 15 amp circuit, run small taps from feeder to each toggle type starter. How would you do it? Any feedback greatly appreciated.
 
Ragin Cajun said:
What's the building layout? Panel location, etc. You could also use manual starters with O/L's all on one circuit.
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It's a factory. Imagine a 40 ft horizontal clock with fans mounted on Ibeam at 12, 3, 6, and 9 o'clock. The panel is sitting right on 12 o'clock. I could move the fans if I have to, into groups of two but this way would give operators equal air circulation.
 
dftmaint said:
Each fans fla is listed as 2.2amp @ 208v three phase. They will be spread out like a clock at 12, 3, 6, and 9 o'clock. Distance from 12&6 and 3&9 will be 40 ft. I would hate to use 4 breakers for a combined total 8.8 amp. I though about manual toggle type starters from a central junction box. One 15 amp circuit, run small taps from feeder to each toggle type starter. How would you do it? Any feedback greatly appreciated.
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I would be inclined toward a single 2 pole CB feeding 4 manual starters.
 
I think it's kind of a glitch in the system but since a 15 amp breaker is the lowest in 240.6 and your loads are only 2.2 amps, one breakers should satisfy 430.52.
From that breaker you could run conductors as best you see fit to your manual starters.
 
augie47 said:
I think it's kind of a glitch in the system but since a 15 amp breaker is the lowest in 240.6 and your loads are only 2.2 amps, one breakers should satisfy 430.52.
From that breaker you could run conductors as best you see fit to your manual starters.
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I'd put it all in one panel. One fuse-switch, four contactors with thermal overloads, and four outgoing cables. Start and stop buttons could be local or remote.
 
Besoeker said:
I'd put it all in one panel. One fuse-switch, four contactors with thermal overloads, and four outgoing cables. Start and stop buttons could be local or remote.
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IMO, the NEC tosses a wrench in that plan. 430.52 limits the SCGF protection to 250% of then FLA (breaker) and 175% (fuse). Since 15 amp is the smallest "standard" breaker, you can use is and get by, but a 6 amp fuse is"standard" you would have to use that and it would be too small for (4) motors.

(thats why I used the term "glitch" in Post 4)
 
dftmaint said:
Each fans fla is listed as 2.2amp @ 208v three phase. They will be spread out like a clock at 12, 3, 6, and 9 o'clock. Distance from 12&6 and 3&9 will be 40 ft. I would hate to use 4 breakers for a combined total 8.8 amp. I though about manual toggle type starters from a central junction box. One 15 amp circuit, run small taps from feeder to each toggle type starter. How would you do it? Any feedback greatly appreciated.
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One consideration though is for maintenance and LOTO reasons - depending on how you set it up, if you want to work on one, all four will get turned off in the right setup. That may or may not be an issue for your application.
 
kwired said:
One consideration though is for maintenance and LOTO reasons - depending on how you set it up, if you want to work on one, all four will get turned off in the right setup. That may or may not be an issue for your application.
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We bought some manual starters with overloads that can also serve as disconnect means. I'm thinking run 14awg to J-Box and using regular wire nuts, parallel into each starter. If we have to work on a fan we can lock out or disconnect the wires at the load side of the manual starters.
 
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