MOTOR VOLTAGE SELECTION

[144x]

I'm a new commer to the world of motors.I recently read in a technical
specification that motors larger than 200 KW shall be connected to the
6.6 KV busbar and the motors smaller than 200 KW shall be connected to the 400 V busbar.can any body guide me to the reason of this choice?
thank you

 

[electricpete]

As horsepower increases, it generally becomes cheaper to buy motors at higher voltages (considering motor purchase cost only).

There may be a lot of other economic factors... also consider the cost of the associated switchgear.

It has been discussed before on this forum.

 

[buzzp]

Higher voltage means the same HP motor will draw less current. So the wire sizes (internal and external to the motor) and sizes of the associated equipment can be smaller and therefore cheaper.

 

[144x]

electricpete can you please guide me to that forum?

 

[electricpete]

Here is one:
thread237-9997
I know there is some more discussion out there but I couldn't find it. Try the search feature.

 

[144x]

thank you thank you thank you

 

[jbartos]

Suggestion: Type "Motor Sizes" keywords in the advanced search and look for Motor Sizes posting