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12 Lead Stator Gennys Discussion

Feel free to discuss the newly posted 12 Lead Stator Generator Schematics, created for ECN by Bjarney.

These items are located in the Technical Reference Area, under the Topic:

12 Lead Stator Generators Schematics

Click the link above to view the Schematics page.

I will get the ball rolling

Bjarney,

Could you please elaborate a bit on these items - especially the Delta Connection, which is labeled as "Derated" and "120/240 VAC 1Ø 3W?

Thanks for the contributions!

Scott35

That 120/240 Single Phase connection has my curiosity.

 
Derating to 2/3 for Edison 1ø 3-wire service on a 12-lead generator comes from not using the efficiency of three phase for loading. Else, a nameplated-30kW/37½kVA genset can only support a 20kW/25kVA load in 1ø 3w service.

Example — Each of six coils in a 30kW stator is rated 5kW. On the 1ø 3w application, referring to the 1ø interconnection schematic, the stator has two sets of three 120-volt windings in a pair of delta groups. For ½ of the windings, T1-T4 coil has a rating of 5kW of load, as do coils T2-T5 and T3-T6. BUT, the interconnected T2-T5/T3-T6 provides 5kW of capacity in phase with T1-T4 coil, for a total of 10kW at 120V. In this case, two 120V 5kW coils can only provide 5kW (not 10) of generator capacity. {Cosine 60° = 0.5} The same holds true for the other half with T8-T11/T9-T12 pair in parallel with T7-T10, providing 5 + 5 or 10kW for each group of three delta-connected coils, with a grand total of 10 + 10 = 20kW for 120/240V 3-wire output.




[This message has been edited by Bjarney (edited 12-20-2004).]

Whould the single phase connection work on a 12 Lead 3Phase motor?

 
Reasonably certain it would not.