shawn.biswas wrote:

Hi Guys,

Trying to model batteries on ETAP for a DC Arc Flash study. Unfortunately the library for batteries on ETAP is very limited and does not have the real life models that we find on site. I'm using Maximum Power Transfer method to calculate my DC IE. My question is that what parameters of the real battery should I keep similar to the ETAP model when finding an alternative ?

Initially I thought that I should pick a battery on ETAP that has similar amp hour rating, specific gravity and Vpc. But unfortunately the amp-hour rating and short circuit ratings on ETAP are never similar to the real life batteries simultaneously. One of the either is always off.

Upon more research, my opinion is that I pick batteries on ETAP that have similar short circuit ratings to my real battery since the Maximum Power Transfer method uses steady state fault current to calculate the DC arcing current, so the amp-hour rating does not play any role. But i'm not sure ? Is that a valid assumption ?

thanks !

Hi Shawn, ETAP has a simple interface that is easy to create libraries based on data sheet. You can contact ETAP helpdesk to request libraries as well. Meantime, depending upon the version you are using , the modeling of batteries is different. For maximum power method Arc flash , the program uses bus nominal voltage and the available short circuit current . For further assistance, you can reach out to ETAP helpdesk that can resolve your queries.

Thank you