help slowing down electric motor

[selmerzodiac]

I recently purchased a dough kneader from france, but it is moving too fast to properly mix the type of bread that I prefer. I originally tried hooking the mixer up to my variac and even when lowering the voltage the mixer speed did not decrease. As I am learning I might need a variable frequency drive, but I have had a hard time finding one that puts out single phase, and I don't want to over buy on features. All I need is a simple device to cut the speed in half (or close to that), and exact speed is not critical. After four hours of calling places looking for one, I figured I should ask someone that knows their stuff if it is even what I really need. Here is what I know about the motor from the manual.
Motor:
Thermal protection, Single phase
110-120 V - 50/60 Hz - 650 W, 6 Amps
1500 RPM (50 Hz) - 1800 RPM (60 Hz)
Speed rotation : 84 RPM (60 Hz).

Let me know if you need any more info on the motor and I will contact the company with specific questions. I would like to thank anyone willing to help in advance, as I in am way over my head here!

 

[LaffeyDD724]

Looks like you might need to go to France and use 50 Hertz current to make your bread.
Tom

None of us is as smart as all of us.

 

[waross]

Looks like the supply voltage frequency might be the key. The motor data says that it will run 300 rpm slower on 50 Hertz.
Now what could be done to lower the supply voltage frequency?
Maybe you could put together some sort of electronic gadget to to drop the supply voltage frequency.

It's called a rotary converter. A motor running on one frequency driving a generator delivering another frequency.
They may use belts or gears to drive the generator at the right speed. It can also be done with direct drive and different numbers of poles on the motor and generator. Direct drive gets big and slow and expensive at 60Hz to 50 Hz.

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

 

[roydm]

Jraef (Electrical),
Yes I understand that the capacitor is there to give you a phase shift at starting, but that's my point. If you had a VFD producing 2 phases 90° apart then you no longer need the capacitor (not all 1 phase motors have one) or for that matter the starting switch.
Each phase could have it's own set of parameters set to match the respective winding.
The motor should develop more torque if both windings were allways in use, rather than one just taking up space.
You should be able to control from 0 - 120 Hz as per 3 phase VFD.
It may possible to use an existing 3 phase drive with just a firmware change, that would keep the cost down.
There are not that many variations on a single phase motor.
Sorry Selmerzodiac, for hijacking your thread.
I am interested to see what others think.
Roy

 

[LaffeyDD724]

Hey, guys I have found something that looks promising, take a look at it and see if it has merit for this application. Check the URL

http://www.anaconsystems.com/text/opti_e2.html

Tom

None of us is as smart as all of us.

 

[itsmoked]

Nice find Laffey.

Pricey!

Of course - it's "over the barrel" pricey.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[jraef]

That Anacon drive is one and the same as the Invertek that Ozmosis mentioned. Anacon just brand lables it from Invertek.

Again, it only works on PSC motors (and Shaded Pole). This motor is not going to be compatible.


"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
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[MintJulep]

How about a co-axial gearbox on the output?

http://www.trivenigroup.com/gears/coaxial-gearboxes.html

Otherwise, sell it and buy what you really need, or learn to like another type of bread.

 

[roydm]

Perhaps a simple overhead fan controller might work. I think they just drop the voltage allowing more slip. It would still run at full speed no-load but dough mixing must require a lot of torque (more slip).
Roy
P.S I will start another thread for single phase VFD

 

[davidbeach]

Overhead fan motors are not the same type of motor as the mixer. What works for one does not work for the other. Fan motors couldn't provide the torque requirements of the mixer. There is also another reason that shaded pole motors are almost exclusively used for fans, they run hot and need lots of cooling air.