Have you looked at snubbers (series RC combination) across the triacs to lower the dvdt voltage rise in the reverse direction ? Rex Pearson ----- Original Message ----- From: "Francois Robbertze" To: Sent: 1 September 2000 18:22 Subject: Re: [PIC]: Switching a 220V AC Electric Bi Directional motor with a Triac/PIC > Hallo again to all PicList members, > > I have difficulties switching a forward and reverse 220V AC bi directional > motor with a pic, triacand optocoupler combination! > > The motor is a typical electric sliding gate opener motor - three wires - > neutral, live(forward) and live(reverse) with a starting cap between forward > and reverse. > > The obvious way is to use two relays. The one relay control the direction > and the other one switch the current... > > I want to do it without relays!!!! > > I have connect two MOC3011 optocouplers and two IT416 triac's to a pic > to > control this motor, but this configuration damage the two IT's...... > I can connect either forward or reverse, but not both!! > > (It seems like the back EMF from the oposite direction switch the motor on > in the opposite direction as well and the motor just vibrates - not sure) > > Attached is a unscrambled version of the layout... > > > Can someone help? > > Kindest regards > > Francois Robbertze > fr10@mweb.co.za > > > -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.