12 wire motor Delta connection

[Jonskelton]

I’ve got a Vernier TV280 metal lathe, it’s got a 3 phase 2 speed motor on, I’m trying to identify the higher speed winding on the motor and connect in delta so I can use a single phase in 3 phase out VFD. The motor has 12 terminals in, no links from new and all 12 connections ran back to a 2 position multipole switch which was the speed selector. I can identify 6 winding with my ohm meter, my question is how do I identify the 3 for 2800 and connect in delta for use with my VFD.

 

[technocrat]

you have a motor where the selector switch changes the number of poles in the motor by series or parallel connection of the windings, giving you a two pole or a four pole motor rather than two conventional three phase motors rolled into 1. Check the rotary selector switch on high speed with the ohm meter to find how to wire the coils. All twelve connections are used at both speeds.

 

[Joe Gwinn]

What is the make and model of the motor itself? A clear picture or two of the motor's nameplate would be useful, maybe essential.

 

[Jonskelton]

What is the make and model of the motor itself? A clear picture or two of the motor's nameplate would be useful, maybe essential.

 

[Jonskelton]

 

[LexD]

Are you sure that it is 2 speed, I can only see one. For this type of motor I use a single phase in 3 phase out VFD where the output is 380V such as an Ecogoo 9100 series drive, that way no changes are needed on the motor.

 

[Jonskelton]

Yeh definitely 2 speed on a selector switch on the front of it

 

[Joe Gwinn]

With six wires, it could well be dual speed. But the data plate does not say. Or that it's three-phase, although at 415 Vac one would expect so.

Now that we know the make and model from the data plate, I'd look that motor up on the manufacturer's website.

 

[LexD]

The symbol next to the 415 stamp my indicate that it is a Double Star Motor.

 

[Joe Gwinn]

The symbol next to the 415 stamp my indicate that it is a Double Star Motor.

Good point. But not a standard symbol?

 

[Jonskelton]

With six wires, it could well be dual speed. But the data plate does not say. Or that it's three-phase, although at 415 Vac one would expect so.

Now that we know the make and model from the data plate, I'd look that motor up on the manufacturer's website.

As far as I can see they went out of business

 

[Joe Gwinn]

As far as I can see they went out of business

Drat! Our European members may know where to look for motor data.

 

[Strostkovy]

I'm assuming it is not connected to the speed selector switch, so we can't get any information by looking at that wiring?

My dad showed me a tool at his job that shows the sequence of windings when you spin a motor shaft by hand. Very neat and useful here.

I am a bit unsure of why 12 wires, unless some are internally connected and it is a 4/6 pole motor.

I'd be interested in seeing how the windings ohm out. That will help you identify pairs that power each winding, and will tell you if any windings are internally connected.

EDIT: I am an idiot and was thinking single phase. 12 wires for 6 windings makes total sense for a dual speed 2/4 pole 3 phase motor. Hopefully the switch is still wired, if not start by ohming out pairs and listing any terminal labels you find.

 

[Almost Retired]

View attachment 380130

it is very likely a consequent pole motor and as suggested above it gives you 4 poles in series
and two poles in parallel for the two speeds
(they seem to have been somewhat common on older machinery)
the double Y symbol is what suggests that to me, as well as being Y wound and not delta
(although the construction may possibly permit a delta connection, but i am doubtful)
look up consequent pole motors on the net, choose an engineering site for reliable and complete info

they are also called constant HP, constant torque, and variable HP and torque
so there are several ways to build them and each requires that all six windings are used in either speed ; series or parallel.
and most of the time the HP will be decreased in the alternate connection, which is required to be shown on the tag in the U.S. but apparently not in some other countries.
this is the second thread involving a motor tag with info similar to this one that i have seen; and several people smarter than me have declared it a consequent pole motor.

 

[Almost Retired]

lets ask @JST
i believe he is one of those that know

 

[LexD]

I think it is one of these.

Dahlander pole changing motor - Wikipedia

en.wikipedia.org

 

[Almost Retired]

As far as I can see they went out of business

as far as identifying windings, you have done that with an ohmeter
connecting them in proper rotation and configuration will require numbers (or other id) on each motor lead
as well as using the connection tag which is normally on another spot on the motor

if you do not have this info, and you have already removed the wires from the drum switch
you will need someone who has the meters and knowledge to re-number for you

 

[Strostkovy]

as far as identifying windings, you have done that with an ohmeter
connecting them in proper rotation and configuration will require numbers (or other id) on each motor lead
as well as using the connection tag which is normally on another spot on the motor

There are winding and phase rotation tools that can be connected to the wires and the lights for each coil will light up in sequence as you rotate the shaft by hand.
I've never used one but my dad showed his to me and it's a very neat little tool.