I purchased 2 lift-master 1355m garage door opener, I was told my a few local installers that they are not working because something in the newer openers detect 50hz instead of 60hz and will not work to prevent damage to the motor. Is it possible to bypass this? or convert the 50hz to 60hz?. I thought about using a AC->DC->AC converter but I dont think i can get enough wattage to make both garage doors work.