3 Phase Siemens induction motor, 6 leads wiring method

Status
Not open for further replies.

kwired

Electron manager
Location
NE Nebraska

meternerd

Senior Member
Location
Athol, ID
Occupation
retired water & electric utility electrician, meter/relay tech
Based on the wiring diagrams in the manual I linked to, there are no 6 lead motors with the numbers the OP stated. There are part winding start, delta and two speed, all of which have 6 leads. The two speed motors have leads marked 1,2,3,11,12,13, so who knows. Others are 1,2 3,7,8,9. I could barely read the nameplate, so maybe your screen is better than mine. Either way, not good to keep smoking starters trying to get it right.
 
Based on the wiring diagrams in the manual I linked to, there are no 6 lead motors with the numbers the OP stated. There are part winding start, delta and two speed, all of which have 6 leads. The two speed motors have leads marked 1,2,3,11,12,13, so who knows. Others are 1,2 3,7,8,9. I could barely read the nameplate, so maybe your screen is better than mine. Either way, not good to keep smoking starters trying to get it right.

Give it up already......There was no evidence that the OP reference to the elads had ANYTHING to do with the factory data and the nameplate and the terminal blocks/peckerhead photos cleraly indicated the following:

The motor is rated dual voltage/frequency.
It is a single winding motor with each end of the three phase windings accessible 3*2=6 and wired/terminated in the traditional EU way of making it suitable for easy Delta/Wye configuration.
 

nazirie

Member
Location
Malaysia
Hi there's.

Long time not up to date. Regard to what we discuss earlier, attach is the full motor name plate. For your info, our motor has 6 leads wire and had been labelled as 1,2, and 3. Each of this pair not a continuity since i already measure with multimeter. How should i connected this 6 leads wire. Should i connected in star or delta. 2013-08-02 12.20.15.jpg
 

kwired

Electron manager
Location
NE Nebraska
Hi there's.

Long time not up to date. Regard to what we discuss earlier, attach is the full motor name plate. For your info, our motor has 6 leads wire and had been labelled as 1,2, and 3. Each of this pair not a continuity since i already measure with multimeter. How should i connected this 6 leads wire. Should i connected in star or delta. View attachment 9110


Your nameplate only says there is 3 leads, you are saying there is 6 leads, something does not add up here.

Has the motor by chance been rewound before?
 

Besoeker

Senior Member
Location
UK
The motor is rated dual voltage/frequency.
It is a single winding motor with each end of the three phase windings accessible 3*2=6 and wired/terminated in the traditional EU way of making it suitable for easy Delta/Wye configuration.
That would be my take.
 

kwired

Electron manager
Location
NE Nebraska
The motor is rated dual voltage/frequency.
It is a single winding motor with each end of the three phase windings accessible 3*2=6 and wired/terminated in the traditional EU way of making it suitable for easy Delta/Wye configuration.

That would be my take.

Please explain how, based on the data plate showing only three leads, to determine how to connect the six leads the OP has encountered? There has to either be the wrong data plate attached or the motor has been rewound differently that its original configuration.

I will let lazlo off the hook a little since we did not see the data plate yet when he had posted.
 

nazirie

Member
Location
Malaysia
Hi guys,

This is a new motor that we never test before. We just bought it and store about one and a half year. The line at nameplate showed only three. They attached two leads together and marked as (1,1), (2,2), and (3,3) and they lug both of this leads. I already test with multimeter that connection (1,1) was not a pair because there's no beep sound hear from my multimeter. Thinking that, there's must be connection configuration about this 6 leads.
 

Attachments

  • Untitled.png
    Untitled.png
    16.5 KB · Views: 1

Besoeker

Senior Member
Location
UK
Please explain how, based on the data plate showing only three leads, to determine how to connect the six leads the OP has encountered? There has to either be the wrong data plate attached or the motor has been rewound differently that its original configuration.

I will let lazlo off the hook a little since we did not see the data plate yet when he had posted.
We haven't seen the inside of the terminal box to see how the terminals are marked.
Three windings, all six end brought out to terminals.
The usual arrangement is that the starts and finishes are arranged as vertical pairs.
Bridge all three finishes for star (Y) and go finish to start, finish to start, finish to start for delta.

Laszlo is right.
The voltages are for 60Hz and 50Hz.
 

kwired

Electron manager
Location
NE Nebraska
Hi guys,

This is a new motor that we never test before. We just bought it and store about one and a half year. The line at nameplate showed only three. They attached two leads together and marked as (1,1), (2,2), and (3,3) and they lug both of this leads. I already test with multimeter that connection (1,1) was not a pair because there's no beep sound hear from my multimeter. Thinking that, there's must be connection configuration about this 6 leads.

What I find odd is that they did not use six different numbers to mark the leads.

My guess is there are two sets of windings connected in parallel, match the numbers from each set and you will get each winding aligned with the right phase.

Very possible this motor could be used as a part winding or a wye-delta starting method but would be simpler to connect if it were marked say 1-6 instead of 1-1, 2-2, 3-3. For across the line starting and normal run tie all same numbers together and one set per phase. For other starting methods - only way to know how to connect is to find out which leads are part of same winding set, as well as determining if it is delta or wye connected as it is shown in the connection diagram.

Since they marked it the way they did, my guess is the manufacturer really did not intend for it to be connected any way but across the line.
 
What I find odd is that they did not use six different numbers to mark the leads.

My guess is there are two sets of windings connected in parallel, match the numbers from each set and you will get each winding aligned with the right phase.

Very possible this motor could be used as a part winding or a wye-delta starting method but would be simpler to connect if it were marked say 1-6 instead of 1-1, 2-2, 3-3. For across the line starting and normal run tie all same numbers together and one set per phase. For other starting methods - only way to know how to connect is to find out which leads are part of same winding set, as well as determining if it is delta or wye connected as it is shown in the connection diagram.

Since they marked it the way they did, my guess is the manufacturer really did not intend for it to be connected any way but across the line.

My guess is that it is connected delta at the factory and the leads are marked as to indicate to WHICH phase they need to be connected. This is what he nameplate connection diagram. Wye/Delta starters becoming scarce and it still produce a jump and problems with open/close transitions and figuring out the timing for switchover.
 

kwired

Electron manager
Location
NE Nebraska
My guess is that it is connected delta at the factory and the leads are marked as to indicate to WHICH phase they need to be connected. This is what he nameplate connection diagram. Wye/Delta starters becoming scarce and it still produce a jump and problems with open/close transitions and figuring out the timing for switchover.


I guess that makes sense, one of the "1" leads should have continuity to one of the "2" leads, that would be the incoming phase 1 to 2 coil. You would have same thing with the other "2" and one of the "3" leads for the second coil, and the remaining "1" and "3" are the third coil.
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
I guess that makes sense, one of the "1" leads should have continuity to one of the "2" leads, that would be the incoming phase 1 to 2 coil. You would have same thing with the other "2" and one of the "3" leads for the second coil, and the remaining "1" and "3" are the third coil.
Good point. In that case the lead numbers are not uniquely identifying the wires as to their internal coil connection but rather by the phase line they need to be connected to.
Since the only intended connection is delta, that does not hinder making a proper connection, but does definitely make it harder to troubleshoot until after you have identified their internal connections with an ohmmeter.
 

nazirie

Member
Location
Malaysia
Thanks all.

i will get some picture in the junction box terminal for further discussion. And i will mentioned to you all the pair for each leads. The worse case when i start the motor using DOL motor starter, the motor run but the contactor burn's up within 60s. So, i identify the problem that the connection configuration false. Think that there's must be phase imbalance since the connection at the junction box wrong.
 

kwired

Electron manager
Location
NE Nebraska
Thanks all.

i will get some picture in the junction box terminal for further discussion. And i will mentioned to you all the pair for each leads. The worse case when i start the motor using DOL motor starter, the motor run but the contactor burn's up within 60s. So, i identify the problem that the connection configuration false. Think that there's must be phase imbalance since the connection at the junction box wrong.


What is burning up contacts or coil? Properly sized contactor shouldn't have much issue with contacts, unless you have "chattering" then they can burn up in a hurry. Is the voltage source sufficient enough to start this motor across the line without excessive voltage drop?
 

nazirie

Member
Location
Malaysia
Contact burn's up. Each of contact melt. I'm think that so much current draw when start this motor. And overload relay didn't sense the overload current since the overload that we used like current transformer type. I jumped to conclusion that there's phase imbalance that's why the overload didn't sense properly and can't cut off the supply voltage. I think that there's no power supply problem since it's burn's up at the rig.
 

kwired

Electron manager
Location
NE Nebraska
Contact burn's up. Each of contact melt. I'm think that so much current draw when start this motor. And overload relay didn't sense the overload current since the overload that we used like current transformer type. I jumped to conclusion that there's phase imbalance that's why the overload didn't sense properly and can't cut off the supply voltage. I think that there's no power supply problem since it's burn's up at the rig.

Is your contactor rated for this size of motor? Even if you have a phase loss, if properly sized it shouldn't burn up contacts, you would likely toast the motor before the contactor if you kept trying to start with a lost phase
 

nazirie

Member
Location
Malaysia
Contactor and overload relay that installed already specified for 150Hp used and i already reconfirm that by referring to the datasheet of the component. Until now, i didn't get answer for this chronology. Since i already mentioned that phase loss,it's possible if the motor run with two phase only, and then that why the contactor burn's up.
 

kwired

Electron manager
Location
NE Nebraska
Contactor and overload relay that installed already specified for 150Hp used and i already reconfirm that by referring to the datasheet of the component. Until now, i didn't get answer for this chronology. Since i already mentioned that phase loss,it's possible if the motor run with two phase only, and then that why the contactor burn's up.
Like I said before, I'd bet the contacts last longer than the motor if you have lost a phase.
 
Contactor and overload relay that installed already specified for 150Hp used and i already reconfirm that by referring to the datasheet of the component. Until now, i didn't get answer for this chronology. Since i already mentioned that phase loss,it's possible if the motor run with two phase only, and then that why the contactor burn's up.

  1. What is the Ampere rating of the contactor?
  2. Just because it is CT driven does not mean that your OL relay has no single phasing protection.
  3. When you lost a phase, you won't be able to restart the motor unless it is driving some fan that makes the motor rotate even when there is no power applied. In other words two phases do NOT provide the rotational torque, but if the rotor is already spinning the motor will turn and accelerate.
  4. As it was pointed out contact burnout would not occur just because single phasing, unless the contacts are already have arcing damage from normal use or chattering and single phasing damage is unlikely.
 
Status
Not open for further replies.
Top