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Craftsman
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Discussion Starter #1
I am trying to make heads or tale of the voltage information on this Bronzoni motor label:

http://www.geocities.com/aaawelder/3phmotor.html

Some of it just doesn't make sense to me. Is the voltage listing Wye/Delta or Delta/Wye or some other configuration. No other wiring info was found in/on the motor.

I intend to use the motor with a Star/Wye configuration with neutral using phase voltage, not phase-to-phase.

thanks for any help.... aaawelder
 

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The link you provided is not working. Maybe we can try it later and see.

Your Quote: I intend to use the motor with a Star/Wye configuration with neutral using phase voltage, not phase-to-phase.

Neutral? On a three phase motor? None of your comments make any sense to me. Give us everything printed on the nameplate. Then tell us what voltage you have.
 

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Craftsman
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Discussion Starter #3
Yahoo is phasing out their geocities hosting service and experiences a lot of down time. You can view the motor label here:

http://aaawelder.rg.angelfire.com/3phmotor.html

Your Quote: I intend to use the motor with a Star/Wye configuration with neutral using phase voltage, not phase-to-phase.

What I meant here is that I will wire the motor in Wye for 120 volt phases instead of 208v but, the question is, what will the total voltage be: 360 or 480 in Wye?
 

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Yahoo is phasing out their geocities hosting service and experiences a lot of down time. You can view the motor label here:

http://aaawelder.rg.angelfire.com/3phmotor.html

Your Quote: I intend to use the motor with a Star/Wye configuration with neutral using phase voltage, not phase-to-phase.

What I meant here is that I will wire the motor in Wye for 120 volt phases instead of 208v but, the question is, what will the total voltage be: 360 or 480 in Wye?
Do you have 120 volt 3 phase? And if you do, I can tell you that you cannot hook it up in a wye configuration. Wye would be for high voltage and delta would be for low voltage. What is the nominal voltage you have to supply this motor. Do you have 3 phase? And is this a project or an application? You have an IEC motor with six leads. While the Europeans call a six lead motor a dual voltage it really is not. A true dual voltage motor will have at least 9 leads. You have six.
If you have 120 volt 3 phase? connect it in delta. Remove the jumpers. If you have 120 volt 3 phase I would be curious as to how. Also, it says 120 volt @ 50 Hz. Do you have a drive or converter? I would like to be of more help but you have to answer the questions.
 

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Super Moderator
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21,650 Posts
The second colum is probably RPM not MIN.
That means that at 60 hertz you have 6 voltage the motor can operate at.
Let's use the first 60 row.
The motor is 4.8 KW runs at 3430 rpm, can be wired to 220 or 380 volt system. Draw 6.8 amps at 220 or 9.7 amps at 380 volts(seems odd, expect lower amps at higher voltage. Are you sure that not 16.8?) and is .89 power factor.
 

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Licensed Electrical Cont.
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7,829 Posts
This is NOT anything you should be messing with if you are not experienced/qualified.
PLEASE call an electrician who know what they are doing. :thumbsup:
 

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Craftsman
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Discussion Starter #7
Here is the quick, I will couple the motor to a prime mover (4hp B&S), drive the motor slightly above operating speed until the motor produces an output voltage on each leg of the WYE. I need to determine the minimum value for the excitation capacitors, mainly voltage rating, for safe operation.
 

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This motor is a basic 6 lead dual-voltage type.

If you want to run it on the lower voltage, connect it delta.

If you want to run it on the higher voltage, connect it wye.

It sounds like you're using it as a generator. If it's turned at 3600 RPM, the output will be 60 HZ. Speed determines frequency, and speed alone.

If it's turning at 3600 RPM, the no-load output will be about 280 or so when connected delta. You'll have 3 phase 3 wire, no neutral.

If it's connected wye, the output will be 3 phase, 4 wire (with a neutral). The voltage will be about 280 from any phase to the neutral, and about 480 phase to phase.

These voltages can vary widely though.

As load increases, voltage will drop, even if speed remains the same. The reason is because there's no field control. In an actual generator, the strength of the field is controlled by the regulator. That's not possible to do with a motor.

When using a motor as a generator, the delta connection is by far the most stable. This is because a delta connection, by its very nature, will tend to balance voltage. A wye doesn't.

Just turning the motor will not make it produce a voltage. It needs to be energized by some source in order to establish a magnetic field. Some motors will accept a short blast of 24 volts DC, others need more. The key here is SHORT!

Remember, you're dealing with lethal voltages here, just because the system isn't connected to a utility doesn't mean it can't do you some serious damage. Be careful. Paranoia is your friend here, always assume that it's 'out to get you'. Don't give it a chance.

Rob
 

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Craftsman
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Discussion Starter #9
You drove it home Rob. My main concern was getting the capacitor values right for excitation and running. I have on hand 3 - 30ufd, 370vac run-caps I will use as a starting value. My calculations give a ballpark value of 12.5ufd.

Voltage regulation is an issue with these machines but this one will not see serious use.

As far as the frequency, I'll have to tweak it until I get the correct engine speed. I understand an electric clocks' second hand will be beneficial here.

Thanks to you Rob, there's nothing left to it but to do it.

Randy Gross
 
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