why is 3 phase preferred?


Old 06-18-11, 07:23 AM
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why is 3 phase preferred?

I am not an electrician and don't completely understand how single and 3 phase works, can someone tell me why 3 phase washers are preferred in a coin op laundry instead of single phase when both options are available? Do you save in the long run? Is there less electrical draw?

All comments are appreciated.
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Old 06-18-11, 08:08 AM
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Three-phase electric power - Wikipedia, the free encyclopedia

That part of the article provides some good information about the advantages of a 3 phase motor over single phase. The rest of the article is informative as well.
Old 06-18-11, 12:58 PM
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The biggest advantage to three-phase motors is that they are self-starting. No staring windings, no starting capacitors and no centrifugal switches or starting relays. All that makes three-phase motors less expensive for any given horsepower AND reduces the failure rate. Added benefit is that they have better starting torque than single-phase motors.
Old 06-19-11, 08:59 PM
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As both guys hit the nail on the spot and with larger coin washer useage they will typicaly use three phase motours they will hold up far much better than single phase motours will do in that evroment.

And many larger coin washer/ dryer will typicaly have three phase supply so it work much easier to use that.

I have done few of them and the larger units will typicaly come with triphase motour but few can get single phase but pretty limited on size espcally if you go over 3 or 5 HP rating. { the last one in state side was big 600 amp service with pretty huge gaz meter in there as well but in France it pretty much all triphase anyway }

the standard size of commercal washer { the same size as home washer } typically use single phase motour but not the same as home duty is they are more beefier ( they use TEFC instead of OFC - open fan cooled )but few case they can order a triphase verison.

Old 06-20-11, 09:42 AM
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One other advantage is that you can often use smaller wires and therefore smaller conduit to install a three-phase motor of equivalent horsepower so the installation can be lower cost and packed more densely into a tight panel or riser area. Three-phase motors place a balanced load on the power company which makes it more efficient for them to provide you quality power service. For this reason many power companies don't even allow single phase motors bigger than 3-5 HP.
Old 06-20-11, 07:06 PM
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( they use TEFC instead of OFC - open fan cooled )
What does TEFC stand for?
Old 06-20-11, 07:46 PM
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Originally Posted by Justin Smith View Post
What does TEFC stand for?
Totally Enclosed Fan Cooled

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