AC or DC

[edsimmons]

I'm fix this Shizuoka ST-N CNC knee mill and I'm not sure if it has an AC or DC motor.

We pulled off the old Shadow controller and added a MachMotion controller w stepper drivers, the guys at MM have helped a lot getting it set up and I've got all the axis jogging and running a few simple programs. The next step is to get the spindle turning. At 1st I assumed it was an AC motor so I was going to control it w a VFD but a Zone member mentioned it may be DC. Soooo.

Here are a few questions.

1) Dose this look like an AC or DC motor? The paint on the number plate is worn off so all I have is the # impressions.

2) If it is DC is there a DC equivalent of a VFD that I can control from my MM controller? If so can you post a link?







Thanks!
Ed

[Al_The_Man]

The fact it looks like pole pieces bolted on from the outside has the appearance of DC?
If you take the terminal cover off and check the connections and/or check for brushes.
If it is DC and the present controller is no good, you could get a Baldor or KB SCR drive.
They come up on ebay all the time, but you will need the HP of the motor.
Al.

[edsimmons]

Oops, the 2nd pic should be this one.

[edsimmons]

The imprinted #'s on the plate look like this. The paint is gone but I could see these #'s

The numbers on the motor info plate look like this

SEN-15V 1.5
CONT 3500
A-H 170 J-K 180
A-H 12 J-K 0.33
6205 6306
77121 16

Thanks
Ed

[Al_The_Man]

DC!
Could be also wound field DC for that size and vintage, the SCR drives referred to earlier include wound field motors.
The SCR bank in the cabinet are probabally the old 3 phase SCR drive?
That looks like a fairly beefy motor, BTW.
Al.

[edsimmons]

Originally Posted by Al_The_Man The SCR bank in the cabinet are probabally the old 3 phase SCR drive?

Thanks Al.

Yes pic 3 is the old electronics, I'd like to ditch the old stuff and go with something more modern and controllable from my MM controller. Any ideas on which SCR would work well for my machine.

Ed

[Al_The_Man]

You would have to come up with the HP or at least an educated guess, I would estimate 2hp if wound field.
If you go to the Baldor or KB site they will list the models.
Al.

[Zig]

The photo shows brushes.. but do they contact slip rings or comutators ?

[samco]

looks like comutators to me.

sam

[jmelson]

Originally Posted by edsimmons The imprinted #'s on the plate look like this. The paint is gone but I could see these #'s The numbers on the motor info plate look like this SEN-15V 1.5 CONT 3500 A-H 170 J-K 180 A-H 12 J-K 0.33 6205 6306 77121 16 Thanks Ed

Taking a wild guess at this, SEN might be "sensor", ie a tachometer with either 15 V / 1000 RPM or 15 V full scale.
Continuous RPM 3500
Armature, 170 V at 12 A = 2040 W = 2.7 Hp electrical input.
Field, 180 V at .33 A = 59 W, which sounds right where I'd expect it.

Jon