IEEE-1584 Bolted Fault Current Spreadsheet

[sharonkr]

Has anyone any experience in using this spreadsheet?
I tried calculating the bolted fault current using this spreadsheet but my results were very different from using another software. Eg, I got around 6kA as my bolted fault level using this spreadsheet and 2.97kA using a fault calculation software.
Help please.

[Homerjs78]

Thats a pretty big difference. Can you provide an image showing the two side by side?

[acobb]

Are you using the same transformer %Z and source %Z in both cases and are both giving you 3 phase fault values? Same x/r ratio?

Alan

[brainfiller]

I have used the IEEE calculator before. It works but there are many little things lurking around that can give you the wrong answer and you may never know it. I was solving a problem last week in a class by hand and someone asked me to try it with the IEEE calculator. I dropped in the numbers and got the wrong answer. I only knew it was wrong because I had solved the problem before. After sifting through all of the various factors including looking at the log (Ia) etc. I saw where it was going wrong. As you gain experience and confidence with the calculator it works well but if people just jump into it.... the old saying "Garbage in Garbage out" still applies. Good Luck with it!

[CMWilson]

I have used the IEEE spreadsheet calculator also. It works but you really need to be careful that the set up is correct - gap - box etc. If you can spring for one of the commercial programs like SKM or EasyPower, it goes much better - but of course it costs $$$

[sharonkr]

Thanks guys.

Please refer to the attachment. This should be a fairly simple as I want to know the fault level after the generator (I have no even reached the tranformer stage)! I must be inputting something wrongly in the IEEE calculator but I just can't seem to find it.

[jghrist]

The "Available MVA" in the IEEE calculator is not the generator rating. It is the available fault MVA. If you are going to use a generator as the source, then divide the rated MVA by the per unit subtransient reactance to get the fault MVA.

[sharonkr]

Thanks for the advice! It really helped!

[Yuna]

i fail to get the IEEE 1584 excel sheet. Does anyone can send it to me? Really thanks for your kindness.

Yuna

[jghrist]

i fail to get the IEEE 1584 excel sheet. Does anyone can send it to me? Really thanks for your kindness.

Yuna

If you purchased the IEEE 1584 standard, you should have gotten the spreadsheet with it. If not, contact IEEE with your invoice information and they will help out.

[arcad]

check AFA v3.0 (http://www.arcadvisor.com/arcflash/arc_flash_analytic.html) The program is based on IEEE 1584 same as the original IEEE spreadsheet and also allows to calculate initial pressure generated by arc blast and arc flash explosive TNT equivalent.