>You are right but how to get it closer? Why do you need it closer ???? with 60.06Hz you are less than 1/10th of 1% off your design frequency, which looks like you are attempting a UPS as a project. Again why do you need the 60hz so accurate. -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics