Single phase motors for a Miehle - specs or recommendations?

jamesanderson84
on 25 Feb 25 (23:09)

I just added two Miehle’s to my existing Miehle and windmill.

They came with three-phase motors - but the building we are in is 240V single phase. I priced out adding a rotary phase converter - but before I pull the trigger I am exploring replacing the three phase motors with single phase.

From what I have read I need to go to 5hp single phase motors - but I can’t figure out what models from what manufacturers would fit.

The Miehle’s are 1942 and 1943 vintage - I don’t have serial numbers to hand but could get them if it’s important.

If anyone has done this swap before I’d love to hear about the experience - or just any recommendations or wisdom of the crowd as to what motors to source.

If anyone has a suitable motor or two in their care then let’s talk…

Thanks

James Anderson
Owner
Saturn Press

rmiller021
on 26 Feb 25 (21:20)

Variable frequency drives are your solution, we have 3 3phase presses far larger than yours running at our shop on single phase 240.

Drives are way cheaper than a new motor.

jamesanderson84
on 2 Apr 25 (16:02)

I took your steer and ordered VFD drives.

Trying to install them - and running into some interesting challenges. The VFD manufacturer (TECO-Westinghouse in this case) says the drive needs to be connected directly to the motor. No switches in the middle.

The Miehles were started (electrically) with a switch on the side of the machine. The black button starts, the red stops. Very standard stuff. The red button could also be pressed by the lever that connects to the door/guard at the front of the machine (a safety feature).

If I follow the VFD manufacturer then I need to bypass the switch and the associated safety feature - and do all motor control through the VFD.

Is that the approach you took with your presses? Do you directly control the electric motor with the VFD? Is there an option I am missing?

Thanks.

rmiller021
on 2 Apr 25 (19:19)

I sent you a message on your Facebook and instagram

I will help you sort it out

I rewired my factory controls on my presses to activate the low voltage inputs on my VFDs.

zbang
on 7 Apr 25 (11:32)

That’s the way to do it, use the old buttons to control the VFD instead of a contactor.

jamesanderson84
on 17 Apr 25 (16:27)

Just to report that the advice rmiller021 gave was spot on - VFDs were the way to go - it took a bit of head scratching for me to get them working - but in the end I wired the old switches up to turn the VFDs on and off to preserve the aesthetics and some safety features on the presses so I am one satisfied poster.