Wiring a 110V two-phase motor?
 

My brother just brought round this motor and I don't know how to wire it up. The reds and blacks appear separate from one another, with red-red and black-black having 300k resistance on my DMM.

EDIT: 300R. See below.

Re: Wiring a 110V two-phase motor?
 

300k sounds a bit open circuit for a motor winding.

I would expect a cap to be involved but the motor plate would normally give a value.

Re: Wiring a 110V two-phase motor?
 

That's what I thought, but since both are the same I wondered if there was something else in the casing, or the inductance was upsetting the reading.

EDIT: my error. I've just done it again and both are 300R! I misread the display, which was 0.370k...

Re: Wiring a 110V two-phase motor?
 

Easily done.

Perhaps it expects an actual 2 phase supply :- https://en.wikipedia.org/wiki/Two-phase_electric_power

Re: Wiring a 110V two-phase motor?
 

I wondered that, but it doesn't look old enough to be genuine two phase. Do you think a capacitor is sufficient to create the phase shift? I suppose I was expecting it to say 'single phase' if it were to be run off normal AC, even with a capacitor. However, there's no difference in resistance to imply a start and run winding. Could I damage it hooking up a capacitor in series with one mains leg and one colour, putting one red to one black and the other mains to the remaining colour?

Re: Wiring a 110V two-phase motor?
 

I think I`d be inclined to put 110 volts across one winding and feed the other via a cap, say 3 or 4uf to start with.

Its a geared motor, can you turn the shaft - if so you may be able to start it by applying power to one winding and giving it a twist.

I think Klaxon were an American company so that could explain the two phase.

Re: Wiring a 110V two-phase motor?
 

Possibly, but the address is Warwick Rd, Tyseley, Birmingham.

Re: Wiring a 110V two-phase motor?
 

Try and connect both windings in series, would be very unusual to have a British made 110V two phase

Re: Wiring a 110V two-phase motor?
 

The motor plate quite clearly states 110 volts 50 cycles, it was presumably intended for some special application.

Re: Wiring a 110V two-phase motor?
 

Would there be any point in testing this item? After all, lets not forget that it would be reliant upon a suitable supply for it to function.

For information purposes however there a system of simplifying small industrial application transformers that function in open delta format. In this the transformer consists of a three phase primary but only two phases are used on the secondary that are configured vectorally 120 degrees apart. They would then be connected in series with the opposite ends used for measurement purposes; hence the reference to open delta.
These same transformers are also used typically in industrial motor control centres for small power and metering requirements. Where, if I recall the secondary windings would be rated 110V divided by root three which imply the ability to test the item but by using two step up transformers; one for each winding.
Does anyone else concur?
Joe

Re: Wiring a 110V two-phase motor?
 

Some interesting ideas here. I look forward to someone concurring or refuting Bookman's hypothesis.

The motor[s] (I think there may be more) are some my brother has from our grandfather. He's interested to see if they work so he knows whether they're junk or not. Perhaps there will be a use for them subsequently, but as I have the variac he was more comfortable with me looking over them. I know no more than that, but I'd be glad to get it turning.

Re: Wiring a 110V two-phase motor?
 

Homes an d light commercial premises in the US get a "110-0-110" supply. Cookers get connected across the full thing and see 220v in reality this may be more like 120-0-120 =240 but it still gets called one-ten and two-twenty.

So the centre tapped supply is two lines of 110, but in opposite phase. Can be called two-phase. Two phase means the phases are 360/2 degrees =180 degrees different. No capacitors needed!

America distributes 110-0-110 services as secondaries on the three phase transformer so you could say they have six phase distribution with each line 110 with respect to ground.

For that Klaxon motor, you have to decide whether it's for 55-0-55 meaning 110v total and two phases Or 110-0-110 it isn't clear from what's on the plate.

David

Re: Wiring a 110V two-phase motor?
 

Although no expert on these sort of things, I would go along with the 180º phase angle. Two phases at 120º would seem rather unbalanced withn the third phase missing.

Re: Wiring a 110V two-phase motor?
 

I'm thinking of a bicycle with the two pedals not 180 degrees opposite :-)

David

Re: Wiring a 110V two-phase motor?
 

Yes, that's not a bad simile. Bicycle pedals at 120º apart would be difficult to use.

Re: Wiring a 110V two-phase motor?
 

180 degree phase shift isn't much good to make a motor turn, I guess it has to have a capacitor in one leg.

Re: Wiring a 110V two-phase motor?
 

Since it's "Klaxon" branded and rotates at 100rpm, I wonder if it was intended to operate the shutters on a pulsed 'nee-naw' type siren? If so, it may have been powered from two of the three phases feeding the blower motor, maybe via a transformer or even taps on the blower's windings. For such a light duty, the extra cost of a winding for the third phase probably wasn't justified.

I think a 180 degree phase difference is unlikely. It's pretty hard to get anything to rotate with two phases 180 degrees apart (do the trig). You need a quadrature component. The standard 120 degrees is fine.

You might be able to get the motor to run using a step down transformer (even less than 110V should be OK for testing) and connecting one winding straight to the supply and the other via a capacitor or inductor to create some phase shift.

Chris

Re: Wiring a 110V two-phase motor?
 

I know it says 100 rpm, but were not two phase motors not used for positioning? -- thinks, was that 90 degree motors? Maybe I should just go quietly.
I just vaguely recall two phases used in process control for positiooning "back in the days".
Les.

Re: Wiring a 110V two-phase motor?
 

Hmmm. Some interesting theories! I can see the difficulty with a 180 degree phase shift if the thing has to rotate. I've briefly applied ~110V in various configurations with no result, neither rotational nor concerning. A capacitor appears the next step. Could I parallel some 0.47µF X-types just to see if it turns, as I haven't any µF level film caps? I've eased the rear bearing as it was very stiff to turn by hand.

Would this be live - winding A - winding A1 - capacitor - winding B - winding B1 - neutral? A series connection with the capacitor between the two windings?

Re: Wiring a 110V two-phase motor?
 

I suspect that this might be expecting a true two phase supply with a 90 degree phase angle between phases. Possibly the red pair to one phase and the black pair to the other phase.
In that case there should be a low resistance between the two red wires and a similar low resistance between the two black wires. Between red and black should be open circuit.

Two phase was never popular in the UK and is now believed to be extinct.
Still exists in the USA, but rare and becoming rarer. Most utilities wont supply 2 phase these days, except to existing customers already so served.

Present day USA mains supplies are usually 240 volts, with an earthed center tap to gibe 120 volts for lighting and small appliances and 240 volts for heavy loads.
Some are two phases and neutral derived from a 4 wire 3 phase system, these give the same 120 volts for lighting and small appliances but with 208 volts for heavy loads rather than 240.
In common parlance in America "two twenty volts" often means a supply that is either 208 or 240 volts but the person speaking does not know or care which. May also refer to an appliance intended to work from either 208 or 240 volts as in "I need to buy a two twenty volt stove"

Neither of the above is a proper substitute for a true two phase supply.

Single phase to true 2 phase converters used to exist, but I doubt that you will find one these days.

Re: Wiring a 110V two-phase motor?
 

I would think it's very likely a 'permanent split-capacitor motor':-

Attachment 218171

I believe the '2 phase' label is to suggest it's a 'symmetrical' type, most suited for reversing applications.

Conect the two windings and the capacitor in a 'triangle' and apply 110v between the junction of the windings and either end of the capacitor. This allows simple reversing with a single pole switch.

Cheers

Re: Wiring a 110V two-phase motor?
 

Yes, that's also how I'd suggest wiring it to try it out.

Chris

Re: Wiring a 110V two-phase motor?
 

Klaxon still exists and is owned by Texecom. They can be found at:

St. Crispin Way
Haslingden
Lancashire
BB4 4PW
UK

Tel: 01706 234800
Email: sales@klaxonsignals.com

Perhaps they may be able to advise on this??

Re: Wiring a 110V two-phase motor?
 

Possibly, but not in view that likely.
Split winding motors usually only have three connections, one end of each winding, with the other ends of the windings connected together internally.
Also such motors are not normally identified as 2 phase.
Capacitor start and capacitor run motors usually have the value of the required capacitor marked on the nameplate.

Re: Wiring a 110V two-phase motor?
 

If you look up Broadmoor sirens, they are Klaxon CS8, the shutters are solenoid driven with spring return.
Having them motor driven would result in the shutters struggling to operate whilst the air is forcing itself against it in the closed position.

Re: Wiring a 110V two-phase motor?
 

I was certainly of the impression that a motor labelled as being "two-phase" was simply that, intended to operate from a two-phase supply. And that the various forms of single-phase induction motors, split-phase, capacitor start, capacitor start and run, etc., were labelled as being "single-phase".

The attached chart, although just a single example, does tend to confirm that impression.


Cheers,

Re: Wiring a 110V two-phase motor?
 

I can't see why.
It works fine on pedal cars!

Re: Wiring a 110V two-phase motor?
 

Generally, UK mains supplies differ from US supplies. We supply, LV - wise, 50Hz, 3 ph.( 120 deg. apart) - - 415V, plain old single phase - - 240V, and - - 480V one phase 3 wire(also known as "Split Phase") which is 180 deg. apart. The US usually have 60Hz 110 - 0 - 110V split phase, and our split phase supplies are 240 - 0- 240V. For example - our nearby rural T/F is 11KV : 240 - 0 - 240V PME), and the nearby farm takes the 480V to run their grain dryer, the farmhouse takes one leg of single 240V, and we get 240V off the other leg. Urban T/F's are generally have secondary o/p's of 415V 3ph, loaded street by street over the three 240V single ph. supplies. Local garages, bakeries, big shops etc., would get the full 3 ph.
Nothing there for a 110V "2ph" American motor, I'm afraid.

Regards, David

Re: Wiring a 110V two-phase motor?
 

If as I suspect this is expecting a true 2 phase supply with a 90 degree phase angle between phases, then it wont work on a USA type single phase 3 wire, 120/240 volt supply.
Neither will it work on the other common USA supply of 120/208 volts, this being two phases and the neutral from a 3 phase 4 wire system with 120 degrees phase angle.

True two phase is believed extinct in the UK and becoming rate in the USA.

Re: Wiring a 110V two-phase motor?
 

It was still used in Belgium and Northern France (Lille/Rysel) when I was there on a School Exchange.

Re: Wiring a 110V two-phase motor?
 

True 2 phase can be generated from 3 phase by means of a SCOTT connected transformer, mainly used in test houses and some labs where it is a reference for in phase and quadrature supplies
ED

Re: Wiring a 110V two-phase motor?
 

The nomenclature on the motor is doubtful. Usually capacitor start/run motors are called 'single phase' because of the supply they run from. If the capacitor is external, the value is marked on the rating plate.

So does 2-phase mean it needed a 2-phase supply, or was it loose language meaningg a capacitive phase shift was needed?

Klaxon sold motors on the general market, they weren't all driving ratcheted diaphragms or sirens.

Re: Wiring a 110V two-phase motor?
 

Klaxon do indeed appear to have been much more than noise manufacurers - Google finds quite a few windscreen motors around for old Rolls Royces, some in old teleprinters, and a possibly similar 'Klaxon geared 110 volt AC motor' in a science museum exhibit demonstrating the principle of the cyclotron!

I wonder if MotorBikeLes (post #18) was on the right track when he mentioned process control. Using 2 phase motors for continuous drive may well be a thing of the past, but 2 phase servo motors seem to be alive and and kicking.

In these, one winding is fed with a fixed ac voltage, whilst the other is driven from an amplifier supplying a waveform at 90° which is varied in amplitude/polarity to control torque/direction. The rotor resistance is optimised for linear relationships between voltage, torque and speed.

https://www.eeeguide.com/two-phase-servomotor/

Although the motor plate states '100rpm' perhaps that just indicates the maximum speed possible. It may be more significant that the H.P. section is left blank.

I'm guessing the high rotor resistance and slip mentioned in the link might mean it's not going to be very useful for anything else, but it might be ineresting to try running it with a capacitor anyway.

Cheers