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2300v motor efficiency continued

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Lostinquebec

Industrial
Nov 10, 2018
22
So, my last thread got closed, but basically I did finally change the settings on the compressor. I successfully reduced the amps by 20 at 2300v. We are no longer blowing air out the wall.
Now, my boss says that we only pay 4cents per kwhr and that we only saved about $5000 a year! Does this sound right?

Lostinquebec
 
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No. It doesn't sound right.
It sounds like a slipped decimal point.
Assuming that the changes did not much affect the power factor:
2300 Volts x 20 Amps x 1.73 = 79.6 kW @ $.04 = $3.18 per hour.
$3.18 per hr x 24 = $76.32 per day.
$76.32 x 365 days = $27,856.80 per year.
That's not the whole picture.
The demand charges in many tariffs often roughly equal the consumption charges.
You may or may not have reduced the demand.
If you do get demand figures, remember to multiply by 12. The demand charges are monthly, not yearly.
A reduction in the consumption of a motor running 24/7 can be expected to reduce the demand.
I expect that the true savings may be more like $50,000 per year.
Be very discrete.
Some bosses don't like employees who are smarter than them.
The money saved doesn't matter to him.
In his mind, it may be that the more money you can save, the poorer he will look to his bosses.
I doubt that he will share the $50,000 figure with his bosses.
When he finds an excuse to let you go, his bosses will not know that you saved them a lot of money.
Polish up your resume!

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Information from the original thread. (OT)
Bill - UPF. 24x365 air compressor operation. Lotta assumption there?
Not a lot, but the comment is valid in this thread.
OT said:
I run a 2300v compressor 24/7 year round and it pulls 110A and blows half of the air out the wall.
OT said:
Induction Motor 600hp,3565 rpm,118 psi,0.993 - 0.998 power factor
Original Thread

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
No offense taken. We can still be friends.
Hint; search "lostinquebec".
The other thread comes up at the top of the list.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
I don't understand how you "changed the amps" on your motor. Is there a VFD or something?


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
 
I reduced the minimum allowable amperage on the machine.

Lostinquebec
 
Hey Waross, thank u so much for the break Down, what’s the 1.73 part of the equation?

Lostinquebec
 
Amps per phase x 1.73 for three phases. (Root 3)


Bill
--------------------
"Why not the best?"
Jimmy Carter
 
There is a minimum Amperage adjustment for the motor, it basically controls the IGV.

Lostinquebec
 
I’m going further on it now, if I use the “dual control” mode, it will totally unload until it’s needed, dropping the Amos to 67A. My problem now, is that the interstage temp goes too high!

Lostinquebec
 
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