3 phase motor wiring?

[Van Huskey]

Is there way to tell if a motor is wired 220 or 440 with only the three legs avaiable to test or see?

I have a large Reuland 3ph motor used on a direct drive machine. The motor only has the three legs coming into the peckerhead so to see what all 9 wires are doing I would have to remove the stator to get to the motor leads. I assume they made the terminations to the 3 legs coming into the peckerhead inside the motor housing since there is a ton of room in there and it is a small peckerhead. I am fine to open it up but prefer to leave well enough alone if I can verify it is wired for low volatge without it. My gut tells me there should be a way but I don't know it.

Anyone?

PS if I crack it open I know what to look for when I can see all 9 wires.

[David Kumm]

I'm assuming the starter is gone and any evidence of the gauge wire it had previously been wired to. If 440 and you start it on 220 it should run very weak but you may not know that until under load. That's all I know. Dave

[Van Huskey]

David, it has a new starter on it, looks exactly like the one below except black. It is completely FILLED with wires. I will try to get pictures of it tomorrow, it isn't like anything I have ever seen before, far more stuff and adjustment pots. I can't find anything about the particular control anywhere, it doesn't seem to be in their current catalog.

[Rollie Meyers]

If there is only 3 wires into the peckerhead, it may be 208 volts or the current NEMA rated voltage of 200V, if this is the case & do not have 208V power then other means will have to be employed to get the voltage reduced, buck/boost transformers are 1 method, since they will not do well & it's a code violation to run one on 240V, Hope this is not the case.

[Van Huskey]

If there is only 3 wires into the peckerhead, it may be 208 volts or the current NEMA rated voltage of 200V, if this is the case & do not have 208V power then other means will have to be employed to get the voltage reduced, buck/boost transformers are 1 method, since they will not do well & it's a code violation to run one on 240V, Hope this is not the case.

It is a dual voltage motor according to the plate so there must be 9 wires coming off the motor? These are unusual motors in that they don't have bearings (it is on a jointer) the bearings are on the journal head only, the rotor is cantilevered off the journal head. There is a lot of extra room inside the motor cover/stator and I am guessing they made the 9 to 3 connection inside the housing since the pecker head is rather small for all those connections especially if you use wire nuts, maybe impossible with wire nuts. In any case I will probably get frisky tomorrow if I have time and open up the motor and see what is in there, if the starter had old school heaters I could just use a size chart to detremine the FLA and compare them to the plate (assumming they are correctly sized). I didn't see anything on the pots that indicate amperage directly and I can't find any documentation for the control panel.

[John McClanahan]

I'm with David on this one. If it starts, but doesn't have any power, then its probably wired for 440.

John

[Rod Sheridan]

Van, what is the overload setting in amperes on the starter, you should be able to match that to the 220 volt or 440 volt rated current of the motor..........Rod.

[Michael W. Clark]

David, it has a new starter on it, looks exactly like the one below except black. It is completely FILLED with wires. I will try to get pictures of it tomorrow, it isn't like anything I have ever seen before, far more stuff and adjustment pots. I can't find anything about the particular control anywhere, it doesn't seem to be in their current catalog.

Van, you may be able to contact a local Square D or Schneider Electric Industrial distributer and they could get you some information on the starter. It may be beneficial to have this even if you determine the voltage without it.

[David Kumm]

Van, Rod was more clear than I but look at both the heaters and the coil. The coil should be set for the correct voltage if dual or be a standard 220 or 440. Dave

[Peter Kelly]

Seems odd that a dual voltage motor would only have three field wires going into the peckerhead. I have seen this on a re-wound motor though.

I suppose if you have a 3ph motor of similar size that you know is wired for 220v, you could use your ohm meter compare the resistance between the two. As above, it won't hurt anything to try connecting it to 220v and see if it runs weak or not.

[Thomas Hotchkin]

Van
You might take a look at this post http://www.practicalmachinist.com/vb...-issue-204769/ My Reuland motor is wired for 220 volts if there is any thing I can check on my motor to help you out, send me a PM. I do have Northfield AC motor Schematic for 9 lead motor connections if you need a copy let me know. Sorry I can't be of more help. Tom

[Van Huskey]

OK I have it figured out...I think. My problem was my only experience with "modern" motor controls have been the cheap $100 versions which are not modular and the pot for thermal protection was direct reading in that it had amps molded in, you just turned the pot to the FLA of the motor. This is a completly modular control center and the over-protection is also modular, point being the pot just had letters not numbers. This module is a Cutler-Hammer. When I looked at it this morning I found the stickers showing a chart with FLA vs pot settings, it is set between the 10.1 and 11.6 amp settings and using linear interpolation it is set pretty much exactly where I would expect 10.4 amps to be which is the FLA of the motor wired for low voltage. The wiring inside the motor control looks very professional so my assumption is the person that wired it knew what they were doing, as I don't think someone that didn't could even begin to wire this. As long as the overprotection is set correctly then it is wired for 220V.

Addressing the 3 wires vs 9 in the peckerhead I am still convinced the 9 to 3 connection is being made inside the motor cover, you would have to be familiar with this motor to understand the room it has inside the housing, otherwise it doesn't makes sense. When I have a little time I may open it up just to satisfy my curiosity about the motor leads but as of now I am 99.9% convinced I have my mystery solved.