Discuss 3ph star delta starter motor drawing high amps in the Electricians' Talk area at ElectriciansForums.net

You have removed the links when you connected the motor to the star delta contactor?
 
Hi yes we was testing separate items out of stores. So not knowing conditions of either item.
Motor was original connected to dol and ran fine.
Obliviosly links were took out to connect to 6 wire star delta.
Thinking must be delta contactor problem.
But just curious now as someone mentioned not all 6 wire motors will run on. Motor reminders confirm motor will run in either.
Anyway items been put back on shelf for another rainy day tidy up.
Thanks for everyone's help.
 
Hi yes we was testing separate items out of stores. So not knowing conditions of either item.
Motor was original connected to dol and ran fine.
Obliviosly links were took out to connect to 6 wire star delta.
Thinking must be delta contactor problem.
But just curious now as someone mentioned not all 6 wire motors will run on. Motor reminders confirm motor will run in either.
Anyway items been put back on shelf for another rainy day tidy up.
Thanks for everyone's help.
Three phase squirrel cage motors will have 6 ends at the terminal block, it's how they are connected that determines how they start and run.
 
My money is it not being wired correctly.

When going into delta it's ending up running on 2 phases. Seen it dozens of times with people who don't have much experience with them.

If it runs fine in star then the motor is fine.
 
star%20delta.png

This is exactly the mistake I presume it to be, should have read the comments before responding.
 
This is exactly the mistake I presume it to be, should have read the comments before responding.
Using the Erroneous diagram , with K3 closed .
Are we looking at a form of symmetry forcing L1 and L3
into a tussle , and possible some circulating currents in the V1 & V2 contacts of K3 ?
Not Pretty !
(Spotted quite a few suspect /tweaked diagrams -Googling!)
 
As static zap said - The erroneous diagram in delta mode connects the U and W windings in parallel across L1 and L3 and shorts the V winding (and connects it to L2 only at one end but no current is drawn from L2). Acting as a three similar winding transformer and Lenz's Law, the alternating magnetic fluxes around each winding must be equal in magnitude and together sum to zero. Thus the currents in each winding are the same in magnitude. The OP sort of told us this in his first post - 'taking 38A on all' - the currents being 120 electrical degrees apart).
 
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