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2300v motor efficiency 6

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Lostinquebec

Industrial
Nov 10, 2018
22
I run a 2300v compressor 24/7 year round and it pulls 110A and blows half of the air out the wall.
I can make some adjustments and get it easily down to 97A.
Can anyone help me with the kind of power and financial savings i'd be looking at?
The Company doesn't seem interested but I feel this could be a significant savings


Lostinquebec
 
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Thank you for your information Brian, and for the addition to my education.
I suspected that there were mechanical issues that were behind this situation.
BrianPetersen said:
There is no easy fix short of replacing the unit. Minor fiddling here and there could save a few percent (as you evidently have shown) but if it is throwing away half the air that it's compressing, the right solution is to replace the entire unit with one half the size ... and preferably with one that's designed to allow variable output in some fashion.
The question to answer now is;
"How much air is being wasted?"
You are correct that there may be a lot of money being wasted.
BrianPetersen said:
Back of notepad calculations with a little bit of guesswork suggests that it's costing about $400,000 per year in electricity to operate this unit. If it's too big by a factor of two, there is money on the table for replacing it.
As well as the energy charges and the distribution charges, this unit may be driving the demand charges up also.
Typically demand charges are based on the monthly peak usage and are a percentage applied to the total power bill.
Even if 25% of the air is being wasted, $100,000 may be enough to purchase and install a used, suitable compressor, with the existing machine kept in reserve.
Big bucks may have to be spent up front, but the payback period may be less than a year and then you are looking at big bucks going forward.
Now the issue may be estimating with reasonable accuracy how much or what percentage of the air is being wasted.
An estimate of the amount of air that was previously used by equipment no longer in service may be a good starting point, but not the end point.
I would not base a recommendation for a major expenditure on the first estimate.
I would use the first estimate to justify the rental of suitable equipment to accurately measure how much air is being wasted.
The figure based on accurate measurements is the figure that may be used to recomment major expenditures.
I hope that this is helpful to you.


Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Consider renting a diesel compressor on wheels until you get a new one installed. Blowing off compressed air is very expensive.
 
In the UK at least, diesel compressors in that size range are disturbingly expensive to rent. We've had a couple on standby from time to time during machine outages and the costs are eye-watering.
 
E-Bay, 400 HP used air compressors;
Prices range from $9500 to $100,000+ USD

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
I believe there is actually a feature on this unit that will unload itself and idle for short periods if not needed. But we're a long ways from that

Lostinquebec
 
Thanks for all the help guys,I believe as long as I dont lower the min amps to the surge point, i'm doing a good thing by getting that blowoff closed
I was just hoping to put a dollar estimate on it.


Lostinquebec
 
See my earlier post - rent the equipment to quantify the potential saving. Shouldn't be a high cost, plus a little bit of engineering / technician time to connect it up. If spending £200 on equipment hire resulted in a £100,000 saving I'd call that a big win.
 
Unfortunately, my workplace disagrees with me, even after I present the data that I have collected. They want that machine blowing the air out the wall (like 600cfm)
Thanks for all the help


Lostinquebec
 
Do you sometimes feel like this?

images_ndb2wk.jpg


At this point I would advise to return the operating points to the original settings and walk away from the issue.
Any change in operating settings may leave you open to be accused of causing any damage, whatever the real reason.
You may be overqualified for your present position, in both ability and in your sense of responsibility.
Good luck.


Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Actually it's ScottyUK's 'toon.
I stole it from the wall of Pat's Pub. grin
Link
Scroll down.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Bill, that was last year's performance appraisal. [lookaround]

LostInQuebec, I think Bill might have summed up your position rather well. Never lose the desire to make things better than they are. [thumbsup2]
 
I'd be considering a move since companies that screwed up are NEVER screwed up in only one glaring way... Think roaches in all the dark crevices.

Keith Cress
kcress -
 
Omg, and now they want to rebuild the other one because the "vibrations" are high! They're at 0.67 mils, alarm is 0.90 and trip is 1.20! I tried explaning that they were relative and change everytime the machine has had work on it.
Now this one will be nice and tight too so we can scream even more air out the blowoff!.🤯👈

Lostinquebec
 
Feeling pretty beat down at this point, it's like I'm surrounded by people that don't know what they should and don't want to, and ur an idiot if u try to think
They actually posted a notice directed at me to not touch the machinery. My response was that we need to get the contractor to come in and take the readings every hour instead of me and get them to start and stop the machinery

Lostinquebec
 
And now its just a poor me rant, I'm sorry guys, i was hoping to do some good

Lostinquebec
 
Do the words;
"Over qualified!" touch a chord?
My sympathies.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
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