Starting of concrete mixer.

[SauravWest]

Dear sirs,

Could you please help me with electrical starting of concrete mixer for site? I think it has to be delta first and star later. How to understand the following picture?

Regards,

 

[rcw retired EE]

I'm assuming you are talking about a reduced voltage starter for an electric motor that runs a concrete mixer. the reason for reduced voltage start is to limit the starting current.

Wye-delta starters start the motor in wye configuration to apply 57% voltage across each winding. At the appropriate time, the motor starter reconnects the motor windings in delta to supply 100% voltage to each winding.