Air Compressor motor help needed. Anyone speaks "electrical" ?

[angelo c]

Which pays very little......

probably as much as a "saw guru" ?
gazzillionaires eh !!!

 

[Fish]

Yeah, and a bunch of lip/flack!!!!

 

[angelo c]

Yeah, and a bunch of lip/flack!!!!

any way...it's always good to hear from you John. thanks for the advise ...

 

[Fish]

John, you seem cranky today....hope all is well.
basically I was looking to ejdumacate muhself some on compressor motors. wtf did the "frame" numbers mean ? and why a 3hp motor is now a 5hp and might even need to be a 7.5hp.... I got the RPM/pulley/shaft thing figured out ok.

I looked into replacing a motor on my compressor long ago, and found that the H.P. numbers allowed to be advertised were totally bogus, and we are not allowed to know what that gibberish actually means, and any replacement motors were either so expensive, or chinese junk, that one could go to Lowes and buy a Campbell Hausfiel or similar new for less money.

 

[Fish]

Like I said, life is too short, unless you have a body shop.......

 

[Fish]

Actually Lowes has some decent chit, you just have to look at what you are looking at.

 

[Fish]

I live in Ingersoll country, so I like that name.

 

[paragonbuilder]

I looked into replacing a motor on my compressor long ago, and found that the H.P. numbers allowed to be advertised were totally bogus, and we are not allowed to know what that gibberish actually means, and any replacement motors were either so expensive, or chinese junk, that one could go to Lowes and buy a Campbell Hausfiel or similar new for less money.

This^^^^^
Ratings are a bunch of crap, especially on China stuff.
The motor shop you took it to didn’t have any info or a motor to replace it for you?

 

[Fresch]

https://www.baldor.com/Shared/pdf/nema_chart_04.pdf

 

[Fresch]

http://rockymountainbaldor.com/wp-content/uploads/2013/06/NEMA-Motor-Overview.pdf

 

[angelo c]

https://www.baldor.com/Shared/pdf/nema_chart_04.pdf

Thank you sir. That's what I was looking for but didnt know I wanted....

 

[Al Smith]

What often happens is usually one or more of several things .The "unloader" stops working which causes the start winding to fail .The start switch fails causing the start winding to fail .The start cap fails causing the start winding failure .Once after all the smoke leaks out of the winding it will never run again . Get on Craiglist and find another motor .

 

[JB-PlantHeirloom]

I would buy a used compressor off CL and use that motor or the whole compressor. Personally if I was going to spend $400 for a motor, which I would not, I would upgrade to a two stage compressor.

You can find fan motors for HVAC condenser units rated the same HP and RPMs as compressor motors and run $80-120 on Amazon. Hesitate before following the CHINenglish instructions that shows wiring the reverse wire to load, it lets the smoke out.

If you have a pulley set up, old table saws (ones made out of all metal) usually have motors that can be used on compressors. The bonus is they have nice pulleys, I have gotten decent money for the ones I sold.

If you go to freight auctions or industrial auctions, you can pick up single compressors or pallets of air compressors cheap.

Storage auctions are iffy because the stuff left behind many times is the stuff that did not run that they could not sell on CL.

If you want to try some local auctions:

https://www.proxibid.com/

You will likely find compressors in warehouse and automobile auctions, though I have found them in food service auctions too.

 

[Bilge Rat]

The frame size is about the intended use.
Find the HP, RPM and voltage then the frame size.
The frame size will give you the shaft dia. and the mounting hole pattern.

Get a Grainger catalog, find the HP/rpm/voltage list then you will see the shaft size/ frame size.
You will find that the frame size can be a few sizes. The difference is in the mounting of the motor.
The plate on the compressor can hold a few different frame # or you can drill a few holes and mount the motor.

A 3hp 215 frame motor is pretty common.

Look at the mounting charts and you will find what you need.

 

[exp500]

Try G..gleing the frame, somewhere I have a pdf list of frame dimensions. I was in same situation as you and got a replacement for about $200. Just had to extend the belt slots.

 

[stretch5881]

A word on chinese motors. I would steer clear, they were using copper coated aluminum in their wiring for a time. I don't know about now.

 

[MACHINE]

I have a blown electrical motor that used to power my shop air compressor. It was a 3hp, single phase,1725 rpm 215 frame motor. I am told a 215 frame is not common to find. I just want to remotor the compressor but some motors are in the $700 range. I am better off buying a new compressor altogether ? I reached out to an Ebay seller and they said a L1510T frame/motor is what I need. also a 7.5 hp....all I want is air ?
what does all this translate into and can an adaptor be purchased or made to use a L1430t motor run on a 215 frame ? Jesus this is confusing.

Stay away from 7.5 hp single phase motor .

5 hp max on single phase

Sent from my SM-G955U using Tapatalk

 

[Al Smith]

Another thing to watch ."Asian motors" they lie about the rating highly over rating it .The true HP is 746 watts per HP .Any thing less just means it can take an over load a few times before the smoke leaks out .

 

[popopboat]

Would avoid not checked "Asian motors" as well if you want reliability and use it a lot...
Cheapstards use small gauge wires which increase heat and decrease windings lifespan, also bearings get shot as grease just melts and escapes.
Some even use aluminium wires, so it barely survives 1 year warranty then burns up.
Step away from brushed motors, if you even find them lol.
As a guy above said, 7.5hp on single phase is way too much, also 5hp is already top even here with 230V.

If you are were satisfied with your compressor up to this time (reffering to mechanical part), i would also suggest rewinding, at someone who knows what he is doing ofcourse and prefferably use resin(or anything else that will prevent wires from rubbing on each other) on windings ... and bearing change ofcourse.
Simply because when rewinding, whole stator is rewinded, rotor cant burn up, and you practically have a new motor.

 

[Al Smith]

This is an old thread but I thought I would add some .What I'm about to say few would understand it but keep in mind I have over 50 years of doing this .In a pinch you can use a 3 phase motor ran on single phase but it takes some circuitry to do .It's composed of several capacitors ,a timer and relay .It will only get about 60% of what three phase would produce .Like 10 HP would do about 6 HP .You can find used three phase industrial motors cheap because few people have three phase and most have no idea how to "Rube Goldberg " them to single phase .Argue about it if you want but I've done it and know it will work .