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Variable speed pump

Variable speed pump

Variable speed pump

(OP)
Anyone know where to find a 10 hp 230 V variable speed swimming pool pump?

RE: Variable speed pump

10 hp 230 volt (single phase) - have you considered the amp requirements to operate?
 

RE: Variable speed pump

Artisi, Great point!  I didn't see it.  Star for U.

'bout 46-50 amps, maybe 150-200 starting then 7000 Watts, right?  Conductors and switchgear will cost more than the pump.
Ouch!

"Make everything as simple as possible, but not simpler." - Albert Einstein (1879-1955)
***************
http://virtualpipeline.spaces.live.com/

RE: Variable speed pump

Actually I calculated 84 amps for the full 10hp -- 746 X 10 / 90% for motor eff. Not sure of starting currents for single phase - but probably very high as it would probably be DOL.  

RE: Variable speed pump

(OP)
Artisi, your calculation might need work, as watts don't equal amps.
Big Inch: it's variable frequency, so I start at lower power, right?

RE: Variable speed pump

One horsepower (HP) equals 746 watts. If a motor is rated at a true 1HP, that means it delivers 746 watts of mechanical power. Since single-phase motors (the kind usually found in consumer power tools) are never 100% efficient in converting electrical energy to mechanical energy, the amount of electrical power consumed by the motor is considerably higher than the mechanical power delivered. In fact, losses from heat, friction, etc., mean that a typical single-phase motor is, at best, around 60-70% efficient. A figure closer to 60% is more realistic for the small induction motors typically found in many home-shop power tools. That means a genuine 1HP motor requires roughly 1250W or more of electrical power to deliver its rated power. In short, you will need at least 10 amps of current at 125V, or 5-plus amps at 250V to realistically deliver a true one horsepower from your motor. This is a good rule of thumb to keep in mind.
Ross

RE: Variable speed pump

Ya, you did say variable speed.  My mistake on the start current.  Are you sure you can't up the supply voltage?

"Make everything as simple as possible, but not simpler." - Albert Einstein (1879-1955)
***************
http://virtualpipeline.spaces.live.com/

RE: Variable speed pump

(OP)
Artisi and BigInch:  I stated up front the supply voltage is 230 V.     

RE: Variable speed pump

We saw that.  increasing the supply V, lowers the amps to more practical levels, which is why most of those size motors will use 3 phase at around 480V, if I'm not mistaken.  

"If stupidity got us into this mess, then why can't it get us out?" - Will Rogers (1879-1935) ***************
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RE: Variable speed pump

hey guys....

mrelet : as i experienced...i didnt find in the market the vfd 10hp single phase..you better to find 230v, 3 phase, and your motor will be also 3 phase...and the amps rated is 28A.....

       hp x 746
______________________ =  27.6A
1.73 x 230v x .8 x .85


 

RE: Variable speed pump

mrelet,

I know for a fact that Goulds G&L has a VFD pump controller called the CPC:

Part# CPC20591
10 HP/ 1 Phase Input (208-230V)
Output FLA (1 Phase Input) = 29.5 A

The output will be 3 phase so you will need a 3 ph pump motor. I think it will run you about $4000.

RE: Variable speed pump

Also mrelet, I am assuming you do in fact have 1 ph supply, although you never stated that.

RE: Variable speed pump

I think enough info has been given - it's now mrelet's move to tell us what in fact he has for a power supply.

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