Domestic single phase to 3 phase advice please

[BotleyBouy]

An inverter for direct connection to a motor does not produce a pure sine wave output, so whatever is controlling the motor speed and torque currently would need to cope with that.

How do I determine this? The machine speed must me controlled by the existing foot pedal which is connected to the lever on the end of the rectangular box under the motor (see photo – nb. the connecting rod is missing).

If you are thinking about directly controlling this existing motor with a new inverter, make sure the insulation class of the motor windings is adequate for the voltage stresses a new inverter will impose, caused by the rapid switching of the drive outputs.

No, I want to retain the existing speed control box and control the machine speed with this via the foot pedal so can I discount this comment? If not, how do I determine whether or not the motor windings are up to the job?

Bernard reckons the motor has an electromagnetic brake. Is that a separate supply? Or is it taken from the motor winding connections?

I don’t know I’m afraid. How do I tell? As far as I can see, there is just one cable going into the motor and that is from the speed controller. All I currently have to go on is the what’s on the data plate above. I'll take a photo of the other data plate shown in the red star above but I'm afraid I won't be able to do that until next Tuesday (nb. that data plate is on the speed controller unit).

As for its former use; I don't think it was from a shoe factory. Judging from the muck I've cleaned out so far I'd guess it was from an upholstery workshop. Of course given how old it is it could have started life somewhere else.

Very many thanks for all the contributions so far.

NB.I did email Efka over a week ago but they haven’t replied.

Here is a technical sheet on the motor https://www.efka.net/fileadmin/downloads/VarioStop-Antriebe/5G82BV2304/EN_TY_5G82BV2304_140600.pdf I'm not sure if this helps much.

 

[crystal ball]

There was a firm that specialised in used machines called Rossendale Sewing Machines a guy called Terry used to run it, very clued up, might still be around

 

[JohnW2]

Here is a technical sheet on the motor https://www.efka.net/fileadmin/downloads/VarioStop-Antriebe/5G82BV2304/EN_TY_5G82BV2304_140600.pdf I'm not sure if this helps much.

I'm no authority on these things, but that data sheet seems to indicate that there is a single-phase version of the 550W motor available ..

Kind Regards, John

 

[BotleyBouy]

That was my interpretation of the info on the sheet but my motor is a VD552 with the 'D' indicating 3-phase and the '2' indicating 2-pole. There's no chance of me finding a single-phase like for like replacement (a VE552).

 

[JohnW2]

... There's no chance of me finding a single-phase like for like replacement (a VE552).

Fair enough - do I take it that you've tried?

Kind Regards, John

 

[bernardgreen]

The motor is only part of the system, it works under the control of the box underneath it. Together they provide some or all of the following functions

THE FOLLOWING FUNCTIONS ARE AVAILABLE AND CAN BE ADAPTED TO THE MACHINE:
- SOFTSTART: On / off; number of stitches and speed at the start of the seam can be selected (no factory set stitches).
- BASIC POSITION: Needle position at stop in the seam up/down.
- BRAKING POWER AT MACHINE STANDSTILL: Braking effect can be set.
- SEWING FOOT LIFT: At stop in the seam automatic / by pedal, after thread trimming automatic / by pedal, start delay from lifted sewing
foot can be set.
- START AND END BACKTACK: Can be set separately, single / double / off, possibility of compensation between forward and backward
section, length of each backtacking section and speed selectable.
- START AND END ORNAMENTAL BACKTACK: Stop time can be set.
- THREAD TRIMMER: On / off.
- THREAD WIPER: On / off.
- STITCH COUNTING: On / off.
- SPEED RANGE: 70 RPM up to 9900 RPM (depending on machine).
- SPEED LIMITATION: Can be varied during machine run and at intermediate stop.
- SWITCHING: Lockstitch machines (replacing 5G62AV) / series 5642/900 (replacing 5G52CP).

SPEED RANGE: 70 RPM up to 9900 RPM (depending on machine). suggests the control box has a variable speed motor controller / driver built into it.


If this machine was originally installed as one of many in a large sewing room then a three phase supply may have been used to ensure the electrical load was spread evenly over the three phase no matter how many machines were being used. There is a small chance that the motor and control box could run on just one phase if the AC input is rectified to a DC supply for the control box's variable speed motor controller / driver .

 

[BotleyBouy]

These motors have been obsolete for a long time. There are a couple on eBay.com for silly money and in the USA. I've checked the existing motor out on a 3-phase supply so know the motor works well. It therefore makes more sense (to me anyway) to find a way of operating the machine with the existing motor rather than take a chance on another one, assuming I could find one.

 

[mattylad]

Try asking rossendale sowing machines as metioned above.
contact = https://rossendale.cylex-uk.co.uk/company/rossendale-sewing-machine-co-ltd-14583636.html

Seems to be not so far from me.

 

[BotleyBouy]

The motor is only part of the system, it works under the control of the box underneath it. Together they provide some or all of the following functions...........

You're absolutely right. The functions you list are set and controlled from yet another box of tricks which is under the left side of the table. This is disconnected at the moment and I'm not to worried if it didn't work as a result of fitting an inverter. These functions are far more sophisticated than I need for my purposes eg upholstery, car seats, boat canopy.

This is a technical sheet for the Schneider unit I posted a link to earlier https://inverterdrive.com/file/Schneider-Altivar-ATV12-Manual Am I right in thinking that we can't know whether this unit would be suitable until I can post up the data plate on the existing speed controller?

 

[BotleyBouy]

Try asking rossendale sowing machines as metioned above. contact = https://rossendale.cylex-uk.co.uk/company/rossendale-sewing-machine-co-ltd-14583636.html
Seems to be not so far from me.

Are they still there? I've looked up the address on Google and it looks like an employment agency now.

 

[crystal ball]

Try asking rossendale sowing machines as metioned above.
contact = https://rossendale.cylex-uk.co.uk/company/rossendale-sewing-machine-co-ltd-14583636.html

Seems to be not so far from me.

That sounds like the feller, really good guitarist if I remember rightly

 

[BotleyBouy]

I doubt this is a just simple electric motor.
For single stitching it must rotate enough to cycle the needle one stitch and then stop with the needle at the top of it's travel. It could be a motor and brake combination,...

This might be relevant to your comment...

The white thing on the balance wheel contains a sensor which ensures the machine always stops at the bottom of a stitch ie at the bottom of the needle stroke. Possibly a safety measure. For what I want to do this feature isn't necessary so if it's lost as a result of fitting an inverter I won't mind.

 

[SUNRAY]

You're absolutely right. The functions you list are set and controlled from yet another box of tricks which is under the left side of the table. This is disconnected at the moment and I'm not to worried if it didn't work as a result of fitting an inverter. These functions are far more sophisticated than I need for my purposes eg upholstery, car seats, boat canopy.

This is a technical sheet for the Schneider unit I posted a link to earlier https://inverterdrive.com/file/Schneider-Altivar-ATV12-Manual Am I right in thinking that we can't know whether this unit would be suitable until I can post up the data plate on the existing speed controller?

That Inverter is potentially the existing 1ph to 3ph converter that you are looking for, the manual you linked to gives the selection of models it covers, there must be a complete model number on it somewhere. Please find it and report back along with the bottom variostop detail (red star) and a good idea of what cables go where.

Many industrial machines have the motor running constantly and all of the control (speed, braking, stopping position etc) is then done in the electrtromagnetic clutch. That may or may not be the case with this machine.

Edits

 

[BotleyBouy]

That Inverter is potentially a 1ph to 3ph converter, the manual you linked to gives the selection of models it covers, there must be a complete model number on it somewhere. Please find it and report back along with the bottom variostop detail (red star) ....

Schneider model number = ATV12H075M2 0.75KW. Here is the same unit on the RS website https://uk.rs-online.com/web/p/inverter-drives/6695783/ . I'll get back to you on the control box data plate.

...... and a good idea of what cables go where.

Please see page 52 https://www.efka.net/fileadmin/down...82FA2315/EN_BAPL_6F82FA2315_1(1)_300301_A.pdf for an idea of where the cables go.

Many industrial machines have the motor running constantly and all of the control (speed, braking, stopping position etc) is then done in the electrtromagnetic clutch.

I think that's how this one works. As soon as I switch the power on I can hear the motor running. It's surprisingly quiet.

Hope this helps a bit.

 

[Simon35]

I would be very reluctant to connect a motor inverter directly to that motor, it's old and very unlikely it's insulation is suitable for inverter operation, and it will fail.

Similarly I would be equally very reluctant to connect a motor inverter to the controller. I doubt those old electronics are going to enjoy the high frequency switching outputs of the inverter.

If you can find a pure sine wave single to three phase converter then that would be the way to go.