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3 Phase Motor Energy Calculation

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PotashMechy

Mechanical
Oct 3, 2013
10
Hi All,

I am not an electrical expert but am trying to calculate the energy consumption per day of a 3 phase motor. My motor is 600V, 30A. I know that the formula for calculating the power is:

kw=(V*A*PF*1.73)/1000

My question is: For a 3 phase motor, do I use the full 600V in my calculation? Or do I use the voltage of the highest leg (or line to line voltage in my understanding) which would be somewhat lower?

Any advice would be appreciated!

Renee
 
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If you want to involve a VFD on a dust collector then why would you only reduce the speed to 1/2 or another arbitrary part speed? Might as well ramp down towards a full stop since it'll be as useless at collecting dust running at part speed as it will be stopped.
 
I agree with Lionel.
Running slow may lead to stratification and eventual plugging of the ducts.
I've seen it a couple of times.
Visualize a crane coming in to assist in dismantling an overhead 30 inch duct so that each section could be manually cleaned of 100% sawdust fill.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Jeff said: 24 May 19 19:44
"Guys (or Gals as the case may be)...

THERE IS NO VFD. That was someone's misinterpretation of the word "drive" which was meant to refer to the MOTOR. The OP stated that there is no VFD so lets not keep going down that rabbit hole..."

I (me, myself and Skogs) used sloppy language and called the motor a drive - because it drives the fan. BUT THERE IS NO VFD. Got it?

Still, the rabbit hole is as crowded as K2.

Gunnar Englund
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
 
My thought and probably Lionel's thought was:
If you are thinking of putting a VFD on a dust collector, stop thinking.
Others besides the OP may be following or browsing this thread.
We don't want someone to get the idea:
"Wow. We have that VFD left over from when we took out the Flux Enturbulator. I can put it on the dust collector and get brownie points for saving money.
Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Got it. But I think that they can get that idea without misreading EngTips.

I had to wait several days for the wood chips to get cleaned from the pipeline with a "bold" bend in a pulp/paper mill only half a year ago. Cold, dark, no schedule. What the management said should take a few hours took almost three days. Guess who had to get the rest of the job done quickly? I know who. There is always plenty of time to do unplanned mechie jobs. Then the sparkies have to reverse time to get in step with the plan. OK, they paid well. But could as well gone home for a couple of days.

Gunnar Englund
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
 
I know the drill.
We had a cyclone plug and back the chips up until they stalled a 300 HP chipper.
They would knock some chips out and try to blow the rest out by running the chipper.
They may have been successful eventually but a supervisor got impatient.
He thought that they could wash the chips out.
Without saying anything to anyone he walked up and threw 5 gallons of water into the running chipper.
The ambient was minus 20 F or minus 29 C.
They brought in a crane to dismantle the entire duct system and rammed each section out individually.



Bill
--------------------
"Why not the best?"
Jimmy Carter
 
That could happen here, too. MBA:s are resourceful and inventive...

Gunnar Englund
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
 
Geeze, next time I'll just let the ill advised operational comments stand as being correct instead of risking posting a correction in case someone gets their panties in a knot.
 
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