eeRyanC
Member
- Location
- Seattle, WA, USA
Hello,
I am an electrical designer working mainly on big box retail projects. As anyone who has worked with energy codes and big box retail knows, light track is one of the greatest challenges for energy code compliance - especially for stores that desire a grid-work of track through-out the space. Integral current limiters and remote current limiting panels help to make compliance possible, but due to the large amount of track I'm working with (roughly 5000' per floor), I'd prefer to use the branch circuit breakers (roughly 250' track per 1P/20A/120V circuit) as the current limiting device, therefore simplifying the system and reducing the number of home-runs. This method of track load compliance works great with all the major energy codes (Title 24, IECC), and for electrical service load calcs [due to 2011 NEC exception to 220.43(B)].
The only issue is that no-one seems to make a 100% rated panelboard with 100% rated 1P/20A branch breakers. I'd prefer 100% rated breakers to the typical 80% rated breakers since I don't have any control how many track heads my client is going to install on the track. I'd like to avoid a panel full of over-heating 80% rated breakers loaded at 90%. Any ideas?
I've considered installing a current limiting sub-panel with 16A breakers, but that is added cost, and if you check the fine print, those 16A breakers are really 80% rated as well so that's not a great solution. A fused branch panelboard may be 100% rated, but it would be a nightmare operationally speaking.
Thanks!
Ryan
I am an electrical designer working mainly on big box retail projects. As anyone who has worked with energy codes and big box retail knows, light track is one of the greatest challenges for energy code compliance - especially for stores that desire a grid-work of track through-out the space. Integral current limiters and remote current limiting panels help to make compliance possible, but due to the large amount of track I'm working with (roughly 5000' per floor), I'd prefer to use the branch circuit breakers (roughly 250' track per 1P/20A/120V circuit) as the current limiting device, therefore simplifying the system and reducing the number of home-runs. This method of track load compliance works great with all the major energy codes (Title 24, IECC), and for electrical service load calcs [due to 2011 NEC exception to 220.43(B)].
The only issue is that no-one seems to make a 100% rated panelboard with 100% rated 1P/20A branch breakers. I'd prefer 100% rated breakers to the typical 80% rated breakers since I don't have any control how many track heads my client is going to install on the track. I'd like to avoid a panel full of over-heating 80% rated breakers loaded at 90%. Any ideas?
I've considered installing a current limiting sub-panel with 16A breakers, but that is added cost, and if you check the fine print, those 16A breakers are really 80% rated as well so that's not a great solution. A fused branch panelboard may be 100% rated, but it would be a nightmare operationally speaking.
Thanks!
Ryan