IEC 9 lead motor connections?

[jraef]

I have one of my technicians in the field working on a motor that has been altered by someone in the past. It is a 4kW 230V motor made in the UK by Alpak according to the nameplate. The connection box has 9 leads coming out, not 12 as I would have expected. The leads have U,V,W 1 thru 3 on them, but the cover of the box has NEMA connection numbers T1- T9 on it with no reference as to how they relate. I can find no reference to Alpak making motors, nor can I find any reference to an IEC motor connection diagram with only 9 leads. We are trying to connect it to 230V

Anyone?

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[jraef]

OK, a correction. The leads are marked U1, U2, U5 then V1,2,5 and W1,2,5. That would indicate to me that there are wires inside that were not brought out, as in U,V and W6, which makes sense now.

Never mind, I think I got it.

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[waross]

Star or Delta?
Star will have one star point made internally and inaccesible.
Delta will have the three corner points of the high voltage connection connected internally and one common lead brought out.
yours

 

[stardelta]

Alpak was a tradename used by the small motor dept of GEC in the UK. It was used for their range of aluminium cased IEC fame motors for the european market They were bought out by the main competitors Brook-Crompton about 10yrs ago and they gradually ran the manufacture of Alpak named motors down and I think they are no longer made. GEC also no longer exists as such, they were bought out by a company called Cegelec. I am not aware of any IEC standard calling for 9 leads out and its probable the motor was specificaly made and destined for use outside Europe. If you let me have the type and serial number I may be able to find out when it was made and who the original customer was via my Brook Crompton agent.

 

[jraef]

Thanks everyone.
Because the machine was sold for the US market and they used a 230 delta / 415 Y motor, they apparently made up the corners of the delta (U1-W6, V1-U6, W1-V6) internally and brought them out only as U1, V1 and W1, leaving it as a 230V only motor. My guess would be that they did this to avoid having any chance of a US electrician someday reading the original nameplate and thinking they could hook up 480 to the high voltage connection pattern. I think they also may have soldered the other connections as well, that would explain why some of the wire numbers were missing and re-applied with after market tape numbers. Someone later tried to re-interpret all this and make the NEMA diagram, which was incorrect because it really was not the same as a NEMA 9 lead motor. It's all sorted out now and running fine. The technician giving me the wrong numbers threw me at first.

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[waross]

It sounds like a standard 9 lead Delta, Dual voltage motor. It would be rated 230-460 volts and be capable of being re-connected for use at 480 volts.

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Does this sketch explain the winding relations?
yours

 

[jraef]

No waross, it is an IEC 12 lead motor, but the OEM only brought 9 of them out. It is now (for US purposes) a single voltage motor.

Eng-Tips: Help for your job, not for your homework Read faq731-376

 

[waross]

Hi jraef
That is standard NEMA practice. In a NEMA motor there are 12 leads or coil ends internally but only nine are brought out. The advantage of the IEC twelve lead motor is that you can change connections from parallel to series and from star to delta. The NEMA 9 lead configuration can be either Star Or Delta, but cannot be changed with the external leads. Either the star or the delta arrangement can be re-connected series or parallel for a two to one voltage ratio. The higher voltage connections are the same but the lower voltage connections are different.
Here are the internal connections for a NEMA delta connected 9 lead motor which I suspect you have.

http://www.firstelectricmotor.com/images/motcon12.jpg

Here are the internal connections for a NEMA 9 lead star motor.

http://www.firstelectricmotor.com/images/motcon11.jpg

This is the parent website.

http://www.firstelectricmotor.com/motor_connections.htm

 

[UKpete]

jraef, with reference to your original post - I'm going to be boring and tell you that IEC 60034-8 "Terminal Markings and Direction of Rotation" shows dual voltage motors (1:2) available in either 9 lead (internal connections as NEMA) or 12 lead (everything brought out) configuration. The 9-lead is either star or delta and must stay that way.

As for British made motors, I'm wearing my black arm-band, all I have left is my pile of specs. Stardelta, any jobs up there for an old Brush bloke?

 

[petronila]

Hello Jraef,

Yes , the leads marks are IEC Standard type, the first to do is find the internal connection (y or D) I think for this small motor the internal connection is wye but check continuity only between U5- V5 and W5 if yes, the internal connection is wye is not you need check continuity between

U5-V1-V2, V5-W1-W2, W5-U1-U2 this conncetion will be delta.

If you find wye connection for 230 V the motor leads connection will be two wyes, L1-- U1-U5, L2-- V1-V5, L3-- W1-W5 and together U2-V2-W2.

If you find Delta connection for 230 the motor leads connection will be two deltas, L1--U1-U5-W2, L2-- V1-V5-U2,
L3-- W1-W5-V2

Regards,
Petronila

 

[petronila]

Jraef,

For nine leads motors The IEC and NEMA( ) equivalents are:

U1 (T1) U2(T4) U5(T7),V1(T2) V2(T5) V5(T8),W1(T3) W2 (T6) W5(T9).

For twelve leads motors add three leads more

U6 (T10) V6 (T11) W6 (T12).

Regards

Petronila

 

[stardelta]

Pete??
Sorry mate, I cant offer you anything but have a look at this link. This was when we lead the world in Machine design and manufacture......way before my time though.

http://www.mvbook.org.uk/

 

[UKpete]

stardelta, thanks. Sadly, I notice that it ends:
"May the next half-century prove a fitting sequel to the first".
There are still little motors here of course, particularly permanent magnet ones, but it's a bit like playing tiddly-winks compared to working on the big machines.
After Brush we moved down to the south coast, and I did a short spell at Allen West before that virtually disappeared. You still see their motor controls and panels all over the place.