ariston 1636 heater element?

hi dan thanks for that have borrowed a circuit tester and there is a circuit through the element , but when i try to test the power through, ie from power to earth it trips the fuse box so the power is getting there ........ have just noticed that the other wire green/brown on the other side of the element isnt plugged into anything have had a look and can only see one place where it could go to .... also the thermostat seems to be in with the element could it be this thats causing the problem ?