Poles in Motor
Poles in Motor
(OP)
So we have an existing motor rated 220/440VAC,3Phase,60Hz,2‐poles then we'll be buying a pump for this but what they can offer are pumps compatible only with a 4-poles bec. the capacity we provided is only suitable for 4-poles, now will there be a problem with that?





RE: Poles in Motor
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
RE: Poles in Motor
The capacity of pump we are looking for should be 320lpm at 11m head.. actually the end user bought first the motor for this w/c is rated 1.5KW H‐line Cooling Pump, 220/440VAC, 60Hz, 2‐poles, 3Phase. Now what suppliers can offer to us is always @1750rpm selection w/c means there’s no pump that can accommodate given duty parameter at 2 pole speed with existing respective motor KW rating. It is not yet connected Sir because we're still looking for suitable pump.
RE: Poles in Motor
2-pole motor runs at just shy of 3000 rpm in the 50Hz world, or just shy of 3600 rpm in the 60Hz world. A 4-pole machine would run at just shy of 1500 rpm or 1800 rpm respectively. Pole count and speed are inherently linked.
New motor time. At that size it shouldn't be particularly expensive.
RE: Poles in Motor
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
RE: Poles in Motor
1> Scotty's suggestion is a good one. Buy a new motor.
However, if you have not yet bought the pump, it may be cheaper and easier to buy a pump and motor combination that will serve your needs and sell the existing motor. (E-bay?)
2> Belt drive a pump from the existing motor as per John's suggestion.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Poles in Motor
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
RE: Poles in Motor
Ask the vendors if they have a 2 pole / 3600 rpm selection that will work.
Or
Find the pump that does the job you want, and buy the correct motor for it. 1.5kW, that's what, $500 if you splurge?
RE: Poles in Motor
flow will increase in proportion to speed ( double)
head will increase in proportion to speed ^2 (i.e quadruple)
power demand from the pump will increase in proportion to speed ^3 ( x 8)
So your original pump will need to be very small (160l/min at 3m head)and will probably not like being run at double the speed.....
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