Need Help!- AC motor wiring

[dan pines]

new old stock Boehm usa (now Baldor) motor, no info on manufacturer's site

1/6 hp, 220v, single phase, 8000 rpm, cont. duty

5 wires, one (green) correctly labeled as ground
no wiring diagram
black + red go to brushes (then to rotor) measure 18.8 ohm
yellow+brown go to 2 interconnected windings (stator?) measure 12.3 ohm
no capacitor, no centrifugal switch inside

220v applied across the brushes just make it hum and vibrate and heat up immediately

I know practically nothing about electrical motors so help would be welcome on the following:

1. what type of motor is this?
2. does it require an outside start and/or run capacitor and if so what are the recommended specs.
3. a wiring diagram

thanks
dan

[Al_The_Man]

If it has brushes it is most likely a DC motor, I don't think Baldor make any universal (AC/DC) motor types.
If so it is no wonder it hummed and got hot.
You need to obtain a DC supply or DC drive for it, The extra pair are probably a DC tach.
KB and Baldor make 240 or 120 mains fed DC SCR drives that may be the cheapest solution to drive it at variable speed.
Al.

[dan pines]

Al
the label definitely says 220v AC, I would post a photo of the label except I don't know how to do it.
the 2 extra wires are definitely not for tach, I opened the motor and they go to the windings
I also tried 24v DC across the brushes - nothing moves/hums/vibrates
dan

[dan pines]

[IMG]d:boehm motor 001.jpg[/IMG]

how can I upload the above photo ?

[dan pines]

I hope this uploads the photo

[Al_The_Man]

If the other pair go to windings on the stator, there are three types of motor I can think of that are AC and use brushes.
One is the universal motor, where the stator is in series with the armature, the second a repulsion start - induction run, although the brushes are usually connected internally, the third is induction start - synchronous run, but this would be slip rings not a commutator.
You will definately have to connect the field somehow before it will run.
If it is a series motor, the field may have been brought out so that reversal could be achieved.
I guess you do not have a Baldor rep where you are?
Al.

[dan pines]

Al

thanks for the prompt replies - but your response is beyond my understanding of motor terminology. slip rings? commutator? series motor? repulsion? armature ? induction start? all these are greek to me..(grin)

the only additional fact I can supply is that there is no electrical contact between the red or black wires (which go to the brushes and then to the rotor i.e. the winding on the main shaft) and the yellow or brown wires which go to the other windings located on 2 half frames surrounding the rotor (called it stator earlier, hopefully that's correct)
So, the brushes are not connected to the other windings. That probably narrows down the options.
On the other hand, is it possible that an external, stand alone, capacitor is required ?(not piggy backed on the motor, there is no place to mount one)

yes, there is a Baldor agent here. He contacted their HQ and came back with "sorry, it is too old and no info available".

[Al_The_Man]

With brushes I don't believe there will be a capacitor involved, it could be a series motor, which means that it would be connected with the stator winding in series with the armature, this four termination method allows reversal as the two connections to the field or the armature pair would have to be reversed.
Take care if you try this as a universal motor runs in a run away condition and rpm is only controlled by load or windage etc.
This is the same type of motor used in portable mains hand tools, vacuum cleaners etc.
Al.

[dan pines]

Al

there is a ventilator mounted on the shaft, I assume this is some sort of load.
I will cross my fingers and may it later in series - I just wonder, if this is the right way why have 4 leads come out instead of just wiring the windings permanently inside the motor and using 2 leads?

regards
dan

[Al_The_Man]

Like I already mentioned, the access to the four leads allows reversing one pair when used in series.
A regular series motor used in appliances there is no need to reverse so only two connections are made and the seriesing is done internally.
The only thing that makes me suspicious is the fact it is only 3000 rpm, that is not alot for a series motor.
Al.

[dan pines]

Al

as I mentioned earlier it says 8,000 rpm. Does that fit in better with the series wiring.

[Al_The_Man]

Must be my eyes failing, (everthing else is )
That would make more sense.
If you have 120 AC available, you could try that first.
Al.