Had it set up to monitor a system that pulled a consistent 1200w at 110v. Came home one day to the system off and the plug for the kill-a-watt melted. There's no way I came close to the 15A max current. 11-12 MAYBE. However, I'm sure if you use it to just measure the instantaneous draw of various appliances, it would be fine, but it doens't work well in a full-time capacity.