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Re: hp -> Watts?

To: shop-talk@autox.team.net
Subject: Re: hp -> Watts?
From: Mike Sloane <msloane@att.net>
Date: Wed, 02 Jun 2004 17:33:30 -0400
Another problem is "ran an extension cord" - you should probably use a 
12 ga. cord no more than 50' long. Your typical Home Depot orange cord 
is probably only 16 ga. - there will be too much resistance in the line 
to carry the full amperage. (Don't ask me how I discovered this.)

Mike

jblair1948@cox.net wrote:

>>Our power went out last night, so I ran an extension cord from the little 
>>1000W Honda (EX, not an EU) generator off down to the sump pump, plugged 
>>it in, and was dismayed to see the pump not work.  Later on, power came 
>>back on and the pump worked fine.
>>
>>I can't imagine that pump is anything more than a 1 hp unit, probably more 
>>like 1/3 or 1/2 hp...  What size generator do I need to make that puppy 
>>work?
> 
> 
> Mark,
> 
> That depends on the pump.  But the conversion for HP to
> Watts is 1hp = 750Watts.  Now for example, a 5hp compressor
> 
> 5hp = 750watts * 5 = 3750Watts or 3.7 KiloWatts (KW).
> For a 110Volt AC line (also called 115 or 120) the current
> would be P=IE (Power[P] = Current[I] * Voltage[E])
> 3750 = I * 110 or I = 3750/110 = 34.1 A with NO safety 
> factor.  The max for a typical household 110 circuit is 20A.
> So you can see that for a 5HP motor, you would need 220V
> service.
> 
> So to answer your question, you need to find the data
> plate on the motor for the pump, and find out how much
> current it draws, and at what voltage.
> 
> Again Power[watts] = Current[Amps] * Voltage[volts].
> So now you can figure out how much power the pump needs.
> If the pump is 220 V and the generator is only 110 then
> the pump won't work.
> 
> Hope this helps
> 
> 
> John
> 

-- 
Mike Sloane
Allamuchy NJ
Email: (msloane@att.net)
Website: <http://www.geocities.com/mikesloane>
Tractor images: <www.fotki.com/mikesloane>
Work: none - Retired!

Distrust all in whom the impulse to punish is powerful.
-Friedrich Wilhelm Nietzsche, philosopher (1844-1900)






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