Removed chassis and found similar failure as yesterday. This time it was the TCS X rotation stage power board that failed. Removed failed board from chassis and re-installed PSL / TCS chassis back in rack so PSL could be brought back up.

For now we are not connecting the TCS Y and X rotation stage field cables to the EtherCat chassis. Further investigation needs to be done to see why the same part (diode) has failed on two separate boards.