1)Check Power supply from Source 2)Check the return path [Neutral (AC) / Ground (DC)] 3)Check for loose connections by pull test (caution:- Switch the PS off before pull test) 4)Check for Short Circuits
Thank you for your sound advise, however you may want to consider the fact that today working on a powered panel aside from the SELV/PELV powered panels has become a daunting tasks thanks to OSHA and Corporate lawyers who see the practice of testing a live panel as a source of high risk issues. Thank you any way