What size cable do I need?

[ian.settle1]

Machine uses total power of 75kva. 22kw. 3 phase.

What size cable will I need for this machine?

If you don't know how to calculate the cable size why did you take the job on in the first place?

 

[ian.settle1]

And if he is a Electrical Trainee the formula should still be on his desk with the ink still fresh

Red to Red Yellow to Yellow and Blue to Bits

 

[electricshock]

I'm not fast tracker. It took me 3 years to get my qual.

I am at the moment on a job connecting up a 11kw 3phase machine which has been moved from one place to another.

 

[KAS1]

This amazes me that I assume a self employed electrician has to ask on a forum this question what on earth would the person employing him to do the work think. He is obviously not up to the standard to take this work on.

 

[MDJ]

I'm not fast tracker. It took me 3 years to get my qual.

I am at the moment on a job connecting up a 11kw 3phase machine which has been moved from one place to another.

Okay lets start again. you have a 3 phase machine which you say has a total running load of 22kw yes? so you need to work out the total load across the three phases first which should give you your Amperage. Once you know what size of mcb you will require you can then use basic calculations to grasp the size of the cable for it, Bearing it in mind the start up current may be large so you may need to consider a d type mcb, if so you need to think about cable sizes again, yes maybe? maybe not? have go at it and if you are close I will chip in and help.

 

[MDJ]

To add there maybe a red hearing in there, there may not, you need to have a think about it and it will do you good.

 

[Badged01]

The handles on it makes it easier to lift it onto your head.

Thats not a hat!! And if shes told you what's in it is a special water based cream for your bald patch .....

 

[MDJ]

Il get my books out.

Great what was the outcome, 1.5mm2, 2.5mm2. 4mm2, 6mm2, 10mm2, 16mm2, 25mm2 other? come on man don't keep us hanging here

 

[guest119]

Like the new selfie Mike :shades_smile:

Boydy

 

[MDJ]

You got bigger problems here than cable size, with a P.F. of 0.3 you're gonna want to work out how you go about correcting that first!

Just realised that myself, I thought the initial sizes looked odd, lol happy days for the op

 

[Badged01]

Just realised that myself, I thought the initial sizes looked odd, lol happy days for the op

He'll sort that with a couple of capacitors ......

 

[LeeH]

He'll sort that with a couple of capacitors ......

I'm waiting for the 'What size capacitors do I need' thread.

 

[D Skelton]

He'll sort that with a couple of capacitors ......

He's gonna have to size them first!

 

[Octopus]

This is an interesting thread.... while I have some sympathy for the OP, its fairly clear that his competence may be lacking. Which just goes to show that its not that easy!

 

[MDJ]

He's gonna have to size them first!

Yup, I just did some calcs myself, too heavy for a sunday morning but hey ho the OP will have to do some for sure.