help needed.......electric motor parts.......

[DEFENDERZOOK]

does anyone here have anything to do with electric motors.....?

the one on my air compressor has died and keeps dropping the circuit breaker every time it turns on.......

its a Brook Crompton Betts........model 922UVB-22....
single phase 240v AC.........


im pretty sure the solenoid pack has packed it in......



where can i get parts from in sydney or on the net.......
does anyone know.......?

[DEFENDERZOOK]

anyone......?

[Blknight.aus]

I do, check the compressor isnt the culprit by draining the air and trying to turn the motoer with a screwdriver (power off first)


Then check the starting capacitor (carefull it can still hold a charge) odds are this is the culprit if you dont see any obvious damage.

Take it down to a motor shop or white goods repair place and they should be able to supply a similar item

other than that new motor time or rewind, Assuming of course that its a belt drive unit and not a married up direct drive jobbie

[sadbenn]

Do you mean capacitors on unit ?
You can get replacement motors. Betts was was taken over by Fasco Dont Know who their agent in Sydney is Brisbane is Edition Adjencies.
Would look at a new unit etc from super cheap Repco etc as the cost could be more than the repair of the motor etc
What size is the unit that You have and type?

[100I]

Ben, why so sad?,, Don't you have a LR?

[Blknight.aus]

Do you mean capacitors on unit ?
You can get replacement motors. Betts was was taken over by Fasco Dont Know who their agent in Sydney is Brisbane is Edition Adjencies.
Would look at a new unit etc from super cheap Repco etc as the cost could be more than the repair of the motor etc
What size is the unit that You have and type?

yeah thats the one, in this day and age they are the achillies heel of electric motors... depending on the nature of the load and a few other blibs and blobs sometimes you will get a slow startup other times you wont get any, aircompressors due to the high friction load to be over come generally wont start but a washing machine motor will spin up slowly and eventually get to going at full speed....

the cap can fail 1 of 2 ways
1. Open Circut its like its not there, if it does this and you can get the motor turning it should keep going and get to full speed

2. Dead short. you might as well plug a fork into the socket and turn it on, it will have the same net effect on the system.

Im not a fully blown leccy but Ive been around the traps with a few and generally if its not the capacitor they just bolt in a new motor.

[abaddonxi]

If it's just a motor start capacitor check out RS -
http://www.rsaustralia.com/cgi-bin/bv/rswww/home.do?cacheID=aunetscape&returningUser=N

They stock stuff that most of the other places have, and an online catalog.

Cheers
Simon

[rick130]

Is the motor blowing the breaker immediately, as if it's a dead short ?
If so, might be more than a cap.
Usually if it's a start or run cap, they will sit and hum and then pop the overload.
Pull your power lead and check your active to earth with your multi-meter. You don't really want any reading under whatsoever. If you are getting a reading, that's not good. ;)

If you suspect a cap, easy enough to check a start and run capacitor with a standard multi-meter.
I made sure 15 years ago that the Fluke I bought had a capacitance tester, but if yours doesn't and most don't, switch to ohms and put your leads across the terminals and the bugger should take a charge, (IIRC, you will see the resistance drop. Been a long time since I've tested one that way :D) Very easy to see on an analogue meter.
If nothing happens the sucker is blown. Usually obvious by a small 'herniation' in the lid, or sometimes they just blow the top clean off. Don't really need to meter those buggers.
FWIW, had a run cap on a Smeg dishwasher blow during the week. Blew the guts clean out the side of it.
If you need to buy a capacitor, either a motor rewinder's or refrigeration wholesaler's usually stock a range of sizes.

If the motors toast, Fasco's can be sourced pretty much from any motor rewinders or wholesalers, but I'd be trying to source a CMG. Oz made and usually significantly cheaper (most all Fasco's are OS sourced these days, usually Asia, not that that's a bad thing ;) ) and bolt straight up to any Fasco/Betts mounting.

[Blknight.aus]

Is the motor blowing the breaker immediately, as if it's a dead short ?
If so, might be more than a cap.
Usually if it's a start or run cap, they will sit and hum and then pop the overload.
Pull your power lead and check your active to earth with your multi-meter. You don't really want any reading under whatsoever. If you are getting a reading, that's not good. ;)

If you suspect a cap, easy enough to check a start and run capacitor with a standard multi-meter.
I made sure 15 years ago that the Fluke I bought had a capacitance tester, but if yours doesn't and most don't, switch to ohms and put your leads across the terminals and the bugger should take a charge, (IIRC, you will see the resistance drop. Been a long time since I've tested one that way :D) Very easy to see on an analogue meter.
If nothing happens the sucker is blown. Usually obvious by a small 'herniation' in the lid, or sometimes they just blow the top clean off. Don't really need to meter those buggers.
FWIW, had a run cap on a Smeg dishwasher blow during the week. Blew the guts clean out the side of it.
If you need to buy a capacitor, either a motor rewinder's or refrigeration wholesaler's usually stock a range of sizes.

If the motors toast, Fasco's can be sourced pretty much from any motor rewinders or wholesalers, but I'd be trying to source a CMG. Oz made and usually significantly cheaper (most all Fasco's are OS sourced these days, usually Asia, not that that's a bad thing ;) ) and bolt straight up to any Fasco/Betts mounting.

the ohms trick wont work with an auto ranging digital multimeter and unless you guess close to the right range on the first go you probabley wont see it on the meter if you manually set the ohms.

The cap can cause the breaker to trip automatically if it failes either side to the casing and the casing is strapped to earth (which is part of the reason washing machine caps these days are in a plastic cover)

to completely eliminate the capacitor disconnect it from the circut (pay attention to orientaion for later assembly and insulate all leads, remeber that the cap can hold a potentaily leathal charge be carefull) and go for a start, if the motor hums at you but doesnt start or starts to move very slowly in both cases its the cap.

[rick130]

the ohms trick wont work with an auto ranging digital multimeter and unless you guess close to the right range on the first go you probabley wont see it on the meter if you manually set the ohms.

works fine with mine, and the ones I've had in the past. ;)


The cap can cause the breaker to trip automatically if it failes either side to the casing and the casing is strapped to earth (which is part of the reason washing machine caps these days are in a plastic cover)
possible, but highly unlikely as I rarely see a metal cased cap, and all the ones I buy (and I bought four just this past week to add to my stock of fifteen or so) are plastic cased.
I'm sure I've had a few, but it is rare for a cap to cause a short to earth in my experience. Usually they pop out the expansion port in the lid of the case where the terminals are in start caps, or blow the lid clean off with electrolyte everywhere. Either way it's usually a quick look tells the start cap is gone without even testing.


to completely eliminate the capacitor disconnect it from the circut (pay attention to orientaion for later assembly and insulate all leads, remeber that the cap can hold a potentaily leathal charge be carefull)
too true, and it doesn't tickle....:eek:


and go for a start, if the motor hums at you but doesnt start or starts to move very slowly in both cases its the cap.not necessarily, other things such as polling of the stator (collapsed bearings, or seized bearings and flogged end housing) can also cause this.

Zook said it was tripping the breaker, I'd still start at at how it's tripping the breaker and go from there.
A lot of these motors used in that sort of application have a thermal overload with a reset button, assuming it does and it's tripping the breaker we have a short to earth somewhere. If it doesn't have an overload and excessive current draw is tripping the breaker due to the motor being stalled, then we start looking at starting devices.

[DEFENDERZOOK]

the bearings are fine......its the two capacitors or whatever they are on the outside.......
one of them is deformed on the end cap......so obviously finally dead.....

its a proper belt driven compressor.......the compressor is fine.......the problem is in the motor.......
it may start and run no problems.......or it may just drop the breaker.......

i can see where its been arcing inside on the end bearing housing near the contact points......
it doesnt have brushes......it has some sort of governor that bypasses the capacitors once it gets up to speed.....