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BrianG · 07.06.2006, 10:01 PM

According to the item description on this site, both the 125B and 80B are supposed to take up to 18 cells or 6s lipo (~22v). That makes sense since both use very similar circuits and FETs; the 80B just uses few FETs for less current capability. However, both lipos and NiXX have higher voltages when fully charged, about 25v. Of course, that full charge wouldn't last long, but it's still higher at first. So, I hesitate to run things to their max ratings (even though I'm sure they figured in a safety margin). Personally, I'd go no higher than ~21v at full charge, which is 5s lipo or 15/16 cells, just to be sure.

As far as where I got the heatsink; it's just a piece of 1/8" thick aluminum angle bar acquired from Menards (like Home Depot, Lowe's, etc). I then attached some computer memory heatsinks to the top of that to give the heatsink a little more surface area for dissipation. The thick angle bar gives the ESC more thermal mass, which helps pull the heat away from the ESC itself.

	(#13)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	07.06.2006, 10:01 PM According to the item description on this site, both the 125B and 80B are supposed to take up to 18 cells or 6s lipo (~22v). That makes sense since both use very similar circuits and FETs; the 80B just uses few FETs for less current capability. However, both lipos and NiXX have higher voltages when fully charged, about 25v. Of course, that full charge wouldn't last long, but it's still higher at first. So, I hesitate to run things to their max ratings (even though I'm sure they figured in a safety margin). Personally, I'd go no higher than ~21v at full charge, which is 5s lipo or 15/16 cells, just to be sure. As far as where I got the heatsink; it's just a piece of 1/8" thick aluminum angle bar acquired from Menards (like Home Depot, Lowe's, etc). I then attached some computer memory heatsinks to the top of that to give the heatsink a little more surface area for dissipation. The thick angle bar gives the ESC more thermal mass, which helps pull the heat away from the ESC itself.