Arc Flash Calculation - IEEE 1584

There is more to arc flash calculations and assessment than some formulas in a spreadsheet. You have the option of buying the IEEE 1584 arc flash standard, or an arc flash calculation program (which is based on the standard). There is also plenty of general information available for free if that is all you are after.

http://www.google.co.nz/search?hl=en&q=IEEE+1584+arc+flash+calculation&meta=&aq=f&oq=

It is advisable to not skimp on safety however.

If you purchase the 1584 Standard from IEEE you get a "Free" spreadsheet calculator. I didn't like the IEEE spread sheet so I wrote my own using the 1583 equations and VB to prove a point to management.

I looked at several commercial software packages and ended up purchasing ISA' EasyPower 8. I've used EasyPower to do analysis of several hundred buses at 20 power plant units from 15 MW GT's to 500MW coal units.

You can also download the web book "Practical Solutions Guide for Arc Flash Hazard Analysis" from ESA. The book is a good starter and has all the equations you need to do manual calcs or make your own spread sheet.

http://www.easypower.com/arc_flash/arc_flash_book.php

I found that the formula in the IEEE 1584 is used to calculate for the less than 15kV system. If i want to calculate the arc flash for the 33kV and above, where should i refer? Thanks..

The IEEE & NFPA equation sets are empirically derived and have statistical limitations. For open air, high voltage calculations you should use the theoretical derived equation by Ralph Lee. As the system voltage and MVA increase, the arc flash becomes less dependent on ambient conditions and the effect of many circuit parameters, such as conductor impedance, are minimized.

The Lee method is described in the IEEE-1584-2002 standard equation 5.4.7, in Ralph Lee's paper "The other electrical hazard:electrical arc blast burns," in the NFPA 70E-2004 Annex D Equation D.8.4 and in the paper "Practical Solutions Guide for Arc Flash hazard Analysis" Equation 3.11 published by ESA and free on their website.

If you do the calculations by pencil and paper of spreadsheet calculator, be sure you have all the units correct. IEEE equations use j/cm^2 and NFPA-70E equations use Cal/cm^2 ans the Incident energy units.

The IEC also has their own AF analysis method, but I've not studied it.

I would highly recommend that you do obtain and read the reference and supporting documents for the analysis method. The equations are simple and appear straight forward, but the devil is in the detail.

Dear Jconn,

Thanks for your information. I will look into it. It helps a lot. Thank you.

Yuna

Keep me posted