M Head - VFD - Normand Electrical Co.

henhen · Oct 16, 2020

Hey guys. First post.
I've got myself a little M Head with a Normand Electrical Motor on it, trying to fit a single phase VFD, can't get my head around the wiring.
The wires (6off) come straight from the motor housing and go into a rotary switch. FWD / STOP / REV. Can't see any numbers on the wires, just the colours and a brand.
Does anyone know how I would convert this for the VFD? ie what colours go together?
Any help would be appreciated, if you need more info, or my question is confusing, just ask :scratchchin:

EDIT:
HP 0.75
Volts 200/220/440

rklopp · Oct 16, 2020

One solution would be to tape the rotary switch in the on position and hook the three VFD phases to the three wires feeding the switch. You can also use a continuity tester to suss out which three-phase input upstream of the switch ends up at which motor wires downstream, then hook the three VFD terminals to each motor wire or wire pair. If you don't know which terminals on the input side of the switch were previously connected to the wall, you're going to need to do more sleuthing. Do you know whether the machine was last run on 220 or 440V? If 440 and you want to run 220, you will need to rearrange the 6 wires from star to delta.

henhen · Oct 17, 2020

Was last ran in 440.
I've identified the pairs, but I think I also need to find start / end of the coil?

rklopp · Oct 17, 2020

henhen said:
Was last ran in 440.
I've identified the pairs, but I think I also need to find start / end of the coil?

Maybe so, unless you luck onto a wiring diagram. No clues on the nameplate or a faded sticker inside the j-box lid? If it's currently wired 440 up to the switch, it seems like you should be able to identify which three coil ends are connected at the star center. Once you do that, you can separate the center and use an ohmmeter to figure out which former star center connection belongs to which outer star connection and thereby isolate the coils, staying mindful of which end of the coil is which. I think you connect the coils head to tail, so to speak when reconnecting in delta for 220 V, thinking of the tail as the former center connection.

JST · Oct 17, 2020

henhen said:
Hey guys. First post.
I've got myself a little M Head with a Normand Electrical Motor on it, trying to fit a single phase VFD, can't get my head around the wiring.
The wires (6off) come straight from the motor housing and go into a rotary switch. FWD / STOP / REV. Can't see any numbers on the wires, just the colours and a brand.
Does anyone know how I would convert this for the VFD? ie what colours go together?
Any help would be appreciated, if you need more info, or my question is confusing, just ask

EDIT:
HP 0.75
Volts 200/220/440

Is that bit about the VFD correct?

Do you mean one running FROM single phase? Or one MAKING single phase?

What then, is the motor?

Six wires can be various things.... it can be a standard single phase 2 voltage motor with start circuit, it can be a 3 phase motor of one of several types. It is not especially likely to be a type that will actually work with a SINGLE PHASE output VFD.

Hopefully you DO mean just one using single phase input. There are actual single phase output units, so it is helpful to be clear what is meant.

henhen · Oct 19, 2020

240v single phase into VFD outputting 440v 3 phase. Sorry for the confusion.
I've managed to sort it and got it running! Just trial and error really, couldn't find anything on the motor to help.
Thanks for the advice!

rklopp · Oct 19, 2020

henhen said:
240v single phase into VFD outputting 440v 3 phase. Sorry for the confusion.
I've managed to sort it and got it running! Just trial and error really, couldn't find anything on the motor to help.
Thanks for the advice!

How did you avoid the error when the magic smoke is allowed to escape? I am curious how you went about it.

henhen · Oct 19, 2020

Followed your advice about the pairs, I knew which were connected to the inner / outer, then read about applying a low voltage so find start/end of the phases. Ie. No voltage induced, swap what could be start/end, hope that helps and isn't confusing. I'm bad with words

DaveKamp · Oct 19, 2020

Sounds like you've figured it out the right way. Fortunately, you won't have to worry about high currents, overloads, and such... the "M" head is certainly not a steel-working monster. When I got mine, a silvery-grey machinist suggested it to be just strong enough to smooth off the top of firm cheese...

I believe the M's intention was for patternmaking... shaping hardwoods, and softer metals. Great for making model airplane parts!

Search

Largest Manufacturing Technology Community on the Web

Search

M Head - VFD - Normand Electrical Co.

henhen

Plastic

rklopp

Diamond

henhen

Plastic

rklopp

Diamond

JST

Diamond

henhen

Plastic

rklopp

Diamond

henhen

Plastic

DaveKamp

Titanium

Similar threads