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View Full Version : Help finding electric motor (Evan,Tiffie,)?



Patch
01-21-2009, 07:13 PM
Hey guys,

I need help locating an electric motor. It is for a special machine application.

Specs:

1/3 to 1/2 hp
C-Face
110v
TEFC
1/2 shaft
1725 to 3600 rpm
60cycle

Motor not to exceed 5" Dia.

Weight preferably under 12 lbs.

What makes finding one such as this differcult is the Diameter needed and the Weight of the unit.

The lighter the better and the smallest diameter possible would be nice.

Please, if known to be post a direct link to motor.

Any help would be appreaciated.

Thanks much

Patch

steve45
01-21-2009, 08:57 PM
What is this used on? Do you have one already? Duty cycle?

Evan
01-21-2009, 09:03 PM
You need to look for something with a NEMA 42 frame.

Willy
01-21-2009, 09:50 PM
What Steve45 said.
The only 42c framed motors that I could find that are close to your specs are either rated for 1/8 hp, or are DC motors if they meet the required hp.
What have you got now?
Are we trying to meet a spec that doesn't exist, or does it just seem that way?

oldtiffie
01-21-2009, 09:54 PM
Can't help Patch - sorry.

Power in OZ is 230/240v 1 phase 50~ unless 3-phase (from the same supply of course.

Patch
01-22-2009, 01:02 AM
Ah, thanks much for the input Evan and tiffie and all.

Here's what I have found so far.
I've located a 1/4 hp-42-1125rpm. Problem is still shaft size and hp. The rpm is livable. Although, 3600 rpm would be ideal.
I also found a 1/3hp Reliance. It had a 6" dia.
It was also to heavy at 18 lbs.

Went to ThomasNet for AC motors. Perhaps a bit of luck there as some manufactures will build to spec and needs.

A topic in discussion with the fellow requesting this assem. He brought up the question of who would make a motor such as this. He rationilized his thoughts fashioned by electric miter saws and circular saws.
These are rated at 1 to 2 hp and have 1/2" arbor shafts.
They also weigh in at less than 8 lbs.

The above is what is hoped to find. Locally,net, or perhaps as a last alternative, to have one built.

Thanks for all the replys thus far.

Patch

Evan
01-22-2009, 01:28 AM
The motors on AC saws, drills and other hand held tools aren't the same as a standard induction motor. They are what is called a Universal motor and work in a similar fashion as a car starter motor. They are series wound with no magnets and will run on AC and DC. They do not have a fixed RPM like a regular induction motor since the line frequency plays no part in determining the operation. They are very powerful for their size but have brushes which is a major life limiting factor.

What you specified are the specsfor a regular induction motor. They require a fair amount of metal to work and can't be made as small for the same power output as a universal motor. A universal motor however, will run at whatever rpm the load permits and when under no load can reach destructive rpms depending on the intended application.

If you aren't tied to an AC induction motor then there are plenty of DC brushless designs that will fill the bill and are much smaller than the space requirement and weight you stated. You can easily find a brushless motor in your required rpm and hp range the size of a beer can.

wierdscience
01-22-2009, 01:59 AM
WEG makes a 48c 1/2hp 1800 rpm 115/230vac motor.

http://www.galco.com/scripts/cgiip.exe/WA/WCat/itemdtl.htm?pnum=.5018OS1BC48-WEG&source=AdWords&gclid=CLaq2eG-oZgCFQIMswodLwIGng#

You will however have to call and specify the mounting type as a C-face and spec your conduit box locations.

Patch
01-22-2009, 02:05 AM
If you aren't tied to an AC induction motor then there are plenty of DC brushless designs that will fill the bill and are much smaller than the space requirement and weight you stated. You can easily find a brushless motor in your required rpm and hp range the size of a beer can.

Could you expand on this a bit given the above mentioned specs needed.

Perhaps this is what is needed.


Thanks much Evan,


Patch

Patch
01-22-2009, 02:12 AM
Thanks for helping to find a motor wierdscience.

The problem with the motor offered by WEG as many others is the weight.
It is in excess of 20 lbs.

I'm needing something under 12 lbs.


Thanks again,

Patch

wierdscience
01-22-2009, 02:15 AM
You would have to see Baldor and up your speed then.They made/make a 1/2hp 115vac motor,but it runs 10,000 rpm.It's only about 3-1/2" OD and maybe 8" long probably 6lbs.Expect $180+ too.


Oh,this might help depending on how many you need.I built a small knife grinder head from one of these a couple years ago.It's a water pump,but with a little lathe work it becomes a small,light weight 1/2hp c face motor.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=1479

If your intrested in sizes PM me and I can measure an extra motor I have.

keelan
01-22-2009, 03:06 AM
Could you expand on this a bit given the above mentioned specs needed.

I'm not Evan, but if you google for BLDC, you will see what he's talking about. Speaking in basic terms, a brushless DC motor is a permanent magnet DC motor, where the excitation of the coils in the rotor is controlled by electronics, rather than by the relation of the brushes to the commutator. It means that you get a very powerful motor for small size (it operates on the the same magnetic principals as a universal motor), but you also get the benefit of speed control. The down side is that in addition to the motor, you need the extra electronics to drive it - a BLDC motor is useless on its own.

Here's a 3/8 HP BLDC motor that measures 4" OD, 5" long, 9 lbs:

http://www.bodine-electric.com/Asp/ProductModel.asp?Context=15&Name=34B%20Series%20BLDC%20Motor&Model=3409&Sort=11277

Oh, and they're expensive.

[edit] The above motor also has a 1/2" shaft.

Evan
01-22-2009, 07:32 AM
Here is a page including a motor that is 5" long by about 3" diameter and draws 348 watts. It's available with integrated drive electronics and has 86% efficiency which make it about 1/3 hp output at 3000 rpm.

http://www.hansen-motor.com/brushless-bldc65s.php

John Stevenson
01-22-2009, 09:21 AM
I know you quoted C face and most things in imperial but the metric 63 framed motors are alloy and 120mm diameter and go up to 1/3HP.

Just an idea ?

.