We did an install 2 months ago. Home was prewired for an outlet out front and the guys put in a GFCI for landscape lighting. I installed a single 600w kichler trans. Also wired on the same breaker are the porch (single coach light) and the foyer light. 2 days ago I added 100w to the system and its now drawing a total of 3.9a on the primary loop. Well within specs. Landscapers tilled an area 2 weeks ago and resodded due to grubs. They tilled in an area i have a 10ga but the system has been performing fine. Tonight I got an email saying my system is causing the breaker in the home to trip when it rains hard. They could not get the breaker to stay on unless they cut off my system. Now i thought if there was a short (im thinking nicked wire when it rains it shorts) it would cause my secondary in the trans to trip or the gfci to pop before the breaker inside blew unless the main breaker is overloaded which it shouldnt be. Any ideas short of pulling up all the wires trying to find this intermittant short ?