cooker calculation - 3 phase

[matt.leung]

Hi all,

Just trying to get my head around this calculation and would be greatful for any guidance.

i have a 3phase 60,000w cooker and just trying to work out the current.

60,000 / 230v = 260.86A per phase

60,000 / 415v = 144.58A per phase

what am i doing wrong, because the numbers seem very high. have i missed out a step?

 

[Andy™]

you missed the square root

so 60000 / ( [square root] x400)

or simply divide kw by 692

 

[ProDave]

60,000/230 =260.86A per phase, single phase.

60,000/400/1.73 = 86.7A per phase 3 phase (1.73 is the square root of 3)

BUT 60KW is a BIG cooker. Are you sure that figure is correct? Must be some commercial monster.

 

[matt.leung]

thanks for the help. yes the cooker is for a pub. there are three of them.

 

[Adrian41uk]

I agree with Dave ..... I think you have mis-read the rating ....... 180kW of cookers in a pub kitchen? Thats gonna be one hell of a hot place to work!

Also, not many pubs can support almost 270A per phase just for the cookers!

 

[Andy™]

3x 60kw cookers is a lot. best check the ratings again

each one would be massive

 

[steptoe]

does anyone else think its an extra 0 ?

6kW would seem a bit more normal.

 

[batty]

I did a job once that had four x 100 amp three phase cookers incoming supply was 200 amp and as you may guess they had regular call outs from DNO. I did tell them before they had the work done it wouldn't work but some people think they know better.

 

[Evans Electric]

Matt, are you sure they're not industrial furnaces !!!! That cannot be right .

Check the ratings mate, then try the following.

Line Amps =

KVA X 1000

----------------------

Line Volts X 1.73 X pf

 

[OnOff]

Hell's Kitchen?

 

[Andy™]

Hell's Kitchen?

no, River Cottage...

 

[daveygh]

are you sure the 60kw is not for gas cookers i.e 60kW (203,000Btu/hr)

 

[bullsta]

I think you're on the right track davey

 

[Evans Electric]

AAAAAAAAAAADmin!!!!!!

Theres a Baggies supporter on the Forum!!!!

 

[batty]

I quite liked bagpuss.