# 220/380 VAC Motor



## chenley (Feb 20, 2007)

Also these German motors ARE rated for 60HZ, not 50.


----------



## Kletis (Jan 18, 2008)

Sounds like a strange couple of motors. I would think that you would be running at about 125% of rated voltage and that is way too much. I would not hook up these motors at this voltage. 

If he insistst you should definitely do it though. Film it and let us know what happens. This could be a great learning exercise for all of us. Sounds like he is too "smart" for his own good...


----------



## Billy_Bob (Aug 25, 2008)

What happens if the motors rotate faster? Any safety issue with the equipment they are connected to? If for some production line thing, those workers might be working quite fast! 

In any case I would write this all out in a letter stating that you advise against doing this, that he is doing this at his own risk, etc. That they could burn out or cause a fire. Then make him sign it.


----------



## John (Jan 22, 2007)

Torque = ((voltage x amps x efficiency)/ 746)*(5252/rpm)

If you use this formula you will find that using 480 V as to using 380V to power the motors will just increase to motor torque. Running a 380-volt motor at 480-volt most likely will not burn the motors up. I have done this a couple times and the motor ran just fine. It will depend on the condition of the 380 volt motors and what they are driving. You may have to change some of the motor controls (fuses, starter overloads, starters and coils, circuit breakers, etc) when you decide what to do. 
It’s an onsite call as to what to do and assume that whoever worked on the machine before you got there ….did it WRONG.

Also look into a buck transformer for the two motors.


----------



## chenley (Feb 20, 2007)

Here's a picture of the control panel to answer a few questions regarding the application:









This is for a grinder system. Pretty much all the scrap wood leftover will be run on a conveyor system to the rear of the building where this machine sits. The 40HP motor runs the main grinder, the parts in the control panel measures current draw and will reverse the motor for about a second and throw it forward again. The other motor is only 1/2hp which runs the hydraulics, that motor I WILL make them replace since that part of the equipment would not be easily replaceable. 

The control wiring is 24VDC and 240AC both coming through the control transformer, which I would have to retap to 480VAC. I do have full prints, a list of components and functions for all the material in the control panel which is a first :thumbup:. 

Kletis: I will definitely film the outcome if they give me the go ahead to run it in this fashion. They probably will, they'll have to buy a used motor either way and it would be difficult for them to sell this motor in the American market. 

Billy_Bob: Yeah, their will be some signatures from the owner, office manager and shop foreman. This equipment is outside and out of harms way so I would probably be the only one in any real danger.

John: Thank you for the formula hadn't used that one in a couple of years. I'll run through the math tonight so I will have more information to present to them. 

Mainly in the control panel I will have to dial the amperages, replace the overload in the top left of the panel, and about three breakers the protect the motors which are rated at the 240VAC amperage. Still looking for other things within the panel that I might need to changeout. Still going over the plans to make sure I didn't miss anything.


----------



## chenley (Feb 20, 2007)

Also if anyone wants to see the prints and components to this equipment. I transferred everything to an AutoCAD file and an Excel file. Just shoot me your e-mail in a PM. I gotta say it is a pretty damn nice setup.


----------



## Billy_Bob (Aug 25, 2008)

Boy I looked at all the stuff in that control panel - relays, transformer, etc. and thought "Oh no... Too much voltage and they might not last very long..."

Then I read this...
[The control wiring is 24VDC and 240AC both coming through the control transformer, which I would have to retap to 480VAC.]

...and thought ok, no problem!


----------



## brian john (Mar 11, 2007)

Get a buck boost transformer and buck the voltage as low as possible. Over voltage will at some point be detrimental to the motors. You can double buck boost and you should be able to drop voltage to 400 VAC. OR you can go to isolation transformers and lower the voltage with double transformation and setting the taps accordingly. Lastly and not sure how this would fly with listing, you could use a isolation transformer 480 120/240 as a buck boost change taps and get to 380 (or close). The kva of the transformer would be based on the amount of voltage lowered by amperage and you would need 3 transformers.


----------



## Kletis (Jan 18, 2008)

brian john said:


> Get a buck boost transformer and buck the voltage as low as possible. Over voltage will at some point be detrimental to the motors. You can double buck boost and you should be able to drop voltage to 400 VAC. OR you can go to isolation transformers and lower the voltage with double transformation and setting the taps accordingly. Lastly and not sure how this would fly with listing, you could use a isolation transformer 480 120/240 as a buck boost change taps and get to 380 (or close). The kva of the transformer would be based on the amount of voltage lowered by amperage and you would need 3 transformers.


 
Good idea!! You would definitely be better off running the motors as close to the rated voltage as possible. I think that by running too much voltage you would have a much shorter life span on the motors.


----------



## micromind (Aug 11, 2007)

These are almost certainly 6 lead motors, low voltage connection is L1=1,6 L2=2,4 L3=3,5 and high voltage connection is L1=1 L2=2 L3=3 4,5,6 tied together. 

If so, they'll work fine on a 240 system, but connecting them to a 480 volt system would likely result in core saturation, along with the accompanying heat and noise. They'd likely work for a while, but not all that long. 

How about the control transformer? Is it 220/380 as well? Blasting it with 480 will result in an increased output voltage. Some of the controls might not like it very much. 

As stated above, buck-boost transformers would be the way to go. If you bucked 48 volts off, you'd be left with 432. A bit high, but likely OK. I'd keep these as small as possible, to minimize the effects of 'plug reversing'. That's plenty hard on any motor, and much worse on one that's run overvoltage. 

Rob


----------



## chenley (Feb 20, 2007)

micromind said:


> These are almost certainly 6 lead motors, low voltage connection is L1=1,6 L2=2,4 L3=3,5 and high voltage connection is L1=1 L2=2 L3=3 4,5,6 tied together.


They're WYE start DELTA run motors, has the U1, V1, W1, U2, V2, W2. Kind of surprised me when I opened up the peckerhead and only saw 6 bolts.


----------



## chenley (Feb 20, 2007)

brian john said:


> Get a buck boost transformer and buck the voltage as low as possible. Over voltage will at some point be detrimental to the motors. You can double buck boost and you should be able to drop voltage to 400 VAC. OR you can go to isolation transformers and lower the voltage with double transformation and setting the taps accordingly. Lastly and not sure how this would fly with listing, you could use a isolation transformer 480 120/240 as a buck boost change taps and get to 380 (or close). The kva of the transformer would be based on the amount of voltage lowered by amperage and you would need 3 transformers.


Thought about using a transformer, except the smallest transformer that would work will need to be 50kVA if I calculated that right for 240VAC. Looking at the prices it seems that replacing the motor with a used one (would be hard to find) would be the best option. 

I do love all the ideas though, will just need to do a cost analysis on it and figure out what would be best for them price-wise. Been a long day, was suppose to be out there, except an emergency call came in about a downed service pole, so I've been playing in the dirt all day, after my hammer drill broke halfway through my first ground rod .


----------



## micromind (Aug 11, 2007)

If a 6 lead motor is wye start/delta run, then it is single voltage. A dual voltage 6 lead motor can be started on wye and run on delta at low voltage only. 

Looking at the picture, it looks a lot like the 2 top contactors are reversing, and the bottom 3 are indeed a wye/delta. I'd be a bit nervous though, there are no mechanical interlocks. If the middle and far right contactors are ever closed at the same time, it'll blow up. This could very easily happen if the start timer failed and was replaced with a standard timing relay. A wye/delta timer always has a short (1/2 second or so) delay during the start/run transition. Scary.

The reversing contactors are not mechanically interlocked either. If both were closed at the same time, a similar explosion would occur. Equally scary. 

I'd like to see the drawing of how they wye/delta start a 6 lead dual voltage motor on high voltage. I could easily be wrong, but I don't think it can be done. If the motor has 12 leads, then it's easy. 

Rob

P.S. If you use buck-boost transformers with 48 volt secondaries, you'll need two 3KVA units to produce 62.5 amps. 5KVA ones will produce 104 amps. 

Rob

P.P.S. If this is connected to a 240 volt system, there are two 3 pole terminal blocks on the bottom. All 6 motor wires land here. Check VERY carefully, most likely the left block has 1-2-3, and the right block has 6-4-5, in that exact order. It's hard to tell from the picture, but phase A must go to 1 and 6, B goes to 2 and 4, and C goes to 3 and 5. 

Rob


----------



## martinre (Aug 3, 2008)

*380 volt motors*

I had to jump in on this one. I would go with a step down transformer, as far as the cost, it should not cost 9000 dollars for a step down transformer for this application. I am very familiar with the 380 volt motors and they will run very hot at 460 volts. A transformer should be around 2000 dollars or less. Try a different supplier.


----------



## brian john (Mar 11, 2007)

50 KVA $1,200.-1,800.00

Buck boost assuming 50KVA at 380 VAC 75 amps X 48 VAC = 3.68 or a 5 using two sets you could drop voltage 96 volts.


----------



## John Valdes (May 17, 2007)

I would not buy anything. First of all, I have never seen a 380 volt motor rated at 60 HZ. The standard will be 380/50Hz - 460/60 Hz. Double check your nameplate. Six lead motors do not come in two versions. They can be used as dual voltage and for wye/delta starting. Wye is high voltage and delta is low voltage. Six lead motors should not be used for dual voltage, but they are marketed as dual voltage. Some IEC motor manufacturers are addressing this issue by changing to 9 lead.

If it were me, I would connect the machine for 460 and wait for the motors in question to die on their own. Then you can replace them with 60 Hz motors. You may be very surprised at how long they may last. You personally may never replace them. So do not buy spares right away. Make sure you know where to get the replacement's when the time comes.
Make sure your customer understands what you plan to do. You are saving him some money up front.


----------



## brian john (Mar 11, 2007)

We just received a job today requesting a 480/400 at 150 kva and 30 kva transformer for EU equipment. Engineer spec'd Square D and included part numbers.


----------



## John (Jan 22, 2007)

John Valdes said:


> I would not buy anything. First of all, I have never seen a 380 volt motor rated at 60 HZ. The standard will be 380/50Hz - 460/60 Hz. Double check your nameplate. Six lead motors do not come in two versions. They can be used as dual voltage and for wye/delta starting. Wye is high voltage and delta is low voltage. Six lead motors should not be used for dual voltage, but they are marketed as dual voltage. Some IEC motor manufacturers are addressing this issue by changing to 9 lead.
> 
> If it were me, I would connect the machine for 460 and wait for the motors in question to die on their own. Then you can replace them with 60 Hz motors. You may be very surprised at how long they may last. You personally may never replace them. So do not buy spares right away. Make sure you know where to get the replacement's when the time comes.
> Make sure your customer understands what you plan to do. You are saving him some money up front.


I will second that.:thumbsup:

Interesting problem so let me add some more variables to the conversation.
I found these wiring diagrams for a star-delta starter and a two speed motor. The wiring of the controls are almost identical. The motor nameplate data needs to be checked and double checked. 

Also a new 3 phase 240 volt service may be an option. It worked before and it should work again this way.

View attachment 648


View attachment 649


Looks almost the same don't they....motors are 6 lead in both controls.:yes::yes:


----------



## micromind (Aug 11, 2007)

The two types of controls are indeed very similar. If the motor is actually 2 speed and has 6 leads, it will be single voltage. 

In looking at the picture as closely as I can, I believe this is a reversing wye start/delta run controller that can be operated at 220 volts only. It could be modified to operate on 380 volts, you'd need to by-pass the wye/delta start system, connect the motor for 380 volts, and start it across-the-lines. You'd also need only 3 wires between the starter and motor. The current set-up has all 6. 

Rob


----------



## chenley (Feb 20, 2007)

This should help the conversation, the wiring diagram for the motors:










e1 - Circuit breaker for rotor motor
e2 - Circuit breaker for hydraulic motor
e6 - Circuit breaker for wormscrew or outfeed conveyor
k1 - Contactor for rotor foward direction
k2 - Contactor for rotor reverse direction
k5 - Contactor for Star/Delta startup
k6 - Contactor for Star/Delta startup
k7 - Contactor for Star/Delta startup
k3 - Contactor for hydraulic motor
k4 - Contactor for outfeed screw conveyor

The motor was hooked up with all six leads, the two large SO cords coming from the bottom of the panel were both hooked to the motor. My boss(father) and I are both going out there this Saturday and having a nice little meeting with them. Mainly about this and a couple of unpaid bills for a new control panel that was built for a piece of equipment and modifying another to be hooked up at 480VAC.

It should be interesting, probably throw a few of your ideas out there. I've already had my father read the posts so far and is in agreement with most everything said. Mainly he is just thinking about the heat produced by I^2R losses. 

I'll keep you guys updated and anymore ideas would be greatly appreciated. I'll definitely have to post a video of it running on YouTube or some other medium for you guys.


----------



## chenley (Feb 20, 2007)

Well I think I came up with a solution to our little problem:

There is a 240VAC three-phase panel that CAN be used. I will be running a sub-panel from the 480VAC panel to the other side of the shop (warehouse), to unload 3-4 pieces of equipment off of the 240 panel to the 480. These pieces of equipment will be easy to change over retap motors and replace a couple of VFD's, changeout heaters, etc. Once all of that is unloaded I will connect this German piece of equipment to the 240VAC panel and leave it be. This, I feel, would be the most cost effective way to make a solution work. 

The contactors not having interlocks really got me to do it this way also the problems with the motors. Considering if we ended up re-wiring within the control panel and the startup switch for the contactors goes out and gets stuck in the closed position bad things happen. Hooking this equipment to 240VAC, I will only be bringing power to this used piece of equipment that THEY provided and not touching the inside wiring of the control panel. This in turn leaves myself and the company out of any legal issues if the panel does happen to blow itself up, since we had nothing to do with the wiring within the panel. 

I will bring up the safety issue of not having interlocks on the contactors with the owners though just to make them aware of the problem. It will be up to them if they have me do anything about it.


----------



## John Valdes (May 17, 2007)

Your drawing is power drawing and not a control drawing. You have interlocks, (contacts) they are electrical interlocks I'm sure. The only time an interlock is required is when you for example don't want contactor "A" to energize when contactor "B" is energized, or visa versa. Your drawing above shows absolutely no control wiring with the exception of the wiring on the XFMR.

Since the 6 lead motors were hooked up using all six leads it was running on 240 or both motors were connected wrong. A six lead dual voltage motor used at 460 volts would have to be connected in wye. Your motors are connected for delta.

Looking at the drawing the only motor that is reversing is the wye/delta motor. This may be the only contactor's that require a safety interlock. Thats why you need a control schematic to understand how this machine works. A power diagram will tell you nothing about the operation.


----------



## chenley (Feb 20, 2007)

I have the control wiring schematic also. It would make quite a long post though, so decided not to post it. Mainly it is the reversing contactors that has me kind of questioning it. I'm sure it is all fine, I've just never seen reversing contactors without a mechanical interlock, then have never dealt with WYE/Delta motors before, a new learning experience. 

We will be hooking it up to 240 this Tuesday and will have it up and running Wednesday. I'll post of video of this thing eating up some wood for you guys if everything goes as planned. :thumbup:

Still have a secondary dust sytem they have installed to hook up temporarily, until we get a plan set in stone for the control panel, which will tie the new and old dust systems together.


----------



## John Valdes (May 17, 2007)

chenley said:


> Still have a secondary dust sytem they have installed to hook up temporarily, until we get a plan set in stone for the control panel, which will tie the new and old dust systems together.


This is were interlocks, timers etc.. are needed. Example: you want the dust collector to start before the grinding starts and you want to make sure you cannot start grinding equipment until the dust collection system is running. You may also want to make the dust collector to run for a few minutes after the grinding stops. You will be using your control schematic to get where you want to be. Good luck and let us know how it goes. :thumbsup:

Ps.....make note of all changes to the drawings. Remember the next guy that comes along.
You are keeping track of your time here right? It is billable, especially if they owe you money.


----------



## chenley (Feb 20, 2007)

Well started up the Grinder motor this morning. It started up fine then when it switched to Delta it shot a spark out the back end up it and tripped the breaker in the panel. Checked all my connections again, and didn't find anything. There were no visible opens in the wiring, nothing. Switched two wires on startup since it did run in backwards on startup. 

Started it again and this time it about blew the breaker on phase A. The motor was re-built by a guy here who said he checked it and that the windings look brand new to him. So we're taking it to him Monday morning to have him look at it again. Seem's like it is going from phase A to ground immediately when it switches to Delta run.

Oh well.


----------



## John Valdes (May 17, 2007)

I think you have it wired wrong. You cannot count on connecting 1to1 2to2 etc.... When this motor was rewound, the motor shop marked the leads 1-6. You cannot expect to just hook up wire for wire.
Since it worked in the wye/start configuration, it is not the motor 

You need a wye/delta start drawing. You have to make sure that when it switches to delta it has numbers 6&1 to line, 3&5 to line and 2&4 to line.

Just for your records the wye is as follows: 4-5-6 go together (third contactor). 1-2-3 go to line.

Wye/Delta starting is one of the most misunderstood motor connection problems I hear about from most everyone. Thank goodness for SS's & VFD's.


----------



## chenley (Feb 20, 2007)

John Valdes said:


> I think you have it wired wrong. You cannot count on connecting 1to1 2to2 etc.... When this motor was rewound, the motor shop marked the leads 1-6. You cannot expect to just hook up wire for wire.
> Since it worked in the wye/start configuration, it is not the motor
> 
> You need a wye/delta start drawing. You have to make sure that when it switches to delta it has numbers 6&1 to line, 3&5 to line and 2&4 to line.
> ...


Well got word back from them they are saying the motor is fried. Found out that all the motor shop did was bake it to get some condensation out and replaced the bearings. I'm not saying the motor was never re-wound just that they didn't do it. Owner's buying a new/used motor to replace it. Not really placing the blame on anyone, just pretty disgruntled about the whole situation.

Let's see if I got this right with what you said. If the motor happened to be re-wound and lets use your example: 6&1 to line, 3&5 to line and 2&4 to line which would make the motor work if the winding were wound that way. So if I wired it 5&1 to line, 3&6 to line and 2&4 to line, would that cause it to start fine on WYE then overload itself on Delta? Pretty much the situation I had?


----------



## DennisR (Sep 6, 2008)

Micromind mentioned before you didn't have mechanical interlocks to prevent wye/delta contactors from simultaneous picking. Maybe your wye coil didn't drop out fast enough. What you need is what we call a "walking beam" in the elevator biz.


----------



## John Valdes (May 17, 2007)

Since you have to replace the motor, will your customer entertain the idea of a soft start instead of the dreaded wye/delta. Then just get a nine lead dual voltage motor.

The SS will be less money than the three contactor arrangement.

Europeans have overkilled so many applications on motor starting. They use alot of wye/delta when a simple contactor could have easily handled the job.
This is your chance to simplify what evidently has become a complicated problem for you.
Whats the HP?

Ps....your connections would not work. Get a small engineering handbook (free) from a supplier. Then you can see how the configurations are laid out.


----------



## chenley (Feb 20, 2007)

It's a 40HP (30kW) motor. They actually had another one laying in a storeroom (1-30HP WYE/Delta and 1-40HP WYE/Delta), I couldn't believe it when they asked me to come out to see if either would work. The 40HP is exactly what I needed, only problem is it's Chinese. It DID have a wiring diagram on the nameplate which had U1, U2, V1, V2, W1, W2, X1, X2, Y1, Y2, Z1, Z2 which after a bit of research on the net is the old IEC motor connections. I've matched them up with the new IEC motor connections and on paper this should work perfectly. 

Although this time I'm checking everything out on the motor to make sure I don't have a winding grounded and none that are phase to phase. Going to borrow a Megger from another shop here and record my readings.

I would love to be able to simplify this hookup although this company is one that is operating on a shoestring. When I finish this equipment hookup and tie in the rest of the dist system they are pulling a loan from the bank to pay us. Seriously, I have word from the manager of commercial loans at the bank they use.


----------



## chenley (Feb 20, 2007)

Wired in the new motor today and everything is running fantastically, just had to switch a couple of leads to reverse rotation of the hydraulic motor. Video to come once I figure out how to post them on something like YouTube.com


----------



## John Valdes (May 17, 2007)

Good Job! How many man hours did it take to figure out it was wired wrong?


----------



## chenley (Feb 20, 2007)

Around 10 hours including talking on the phone with the motor shop, owner, shop foreman. Testing the new motor and wiring in both motors. Billed for everything.

The motor shop is stating that it was a "power surge" that killed the motor. 

Although I do have motor wiring diagrams for all motors connections: NEMA, IEC and old IEC that will be left in the van. Been quite a learning experience.


----------

