Three phase current motor 400v

[brizospark]

In a 23 kw three phase motor will each phase have 100a?

 

[telectrix]

no....

 

[malcolmsanford]

no....

next............................

 

[Knobhead]

23KW @ 400V, .9PF and 95% efficiency = 38.4A

Must get my eye's tested
View attachment 11613

 

[Kenny.]

I dont know about a 23 kW but a 22 kW 3 phase Motor has a flc of 41A per phase

 

[malcolmsanford]

How did you work that out Kenny, was you using UK 400 volts or a PF

 

[telectrix]

bearings must be tight. i nget 35A@ pf 0.9

 

[Knobhead]

Time to buy a new motor I think.

 

[brizospark]

bearings must be tight. i nget 35A@ pf 0.9

Can anyone explain the equation to work this out

 

[telectrix]

P = sq.root 3 x I x pf.

so I = P/(1.732 x V)

I = 23000/ (1.732 x 400) = 33.2A (not allowing for pf)

 

[brizospark]

P = sq.root 3 x I x pf.

so I = P/(1.732 x V)

I = 23000/ (1.732 x 400) = 33.2A (not allowing for pf)

thanks for that, so how would the calculation be affected by pf?

 

[telectrix]

if , say the pf was 0.8 ( about the worst for a motor), then toy would divide thew answer again by 0.8. i.e in the above case , 33.2/0.8 = 41.5A. in short, the pf causes the current drawn to increase.

 

[brizospark]

thanks for that telectrix

 

[telectrix]

divide