by Jack Goho
Gideon Analytical Laboratories received several lighting tracks for failure analysis. They all had what appeared to be arcing which caused severe copper pitting, melting of the Noryl, and distortion of the power bus bar. The neutral bus was also pitted but not nearly as bad as the power rail. Electrical arcing is an electrical breakdown of a gas that produces an ongoing electrical discharge. The current through a normally non-conductive medium such as air produces a plasma; the plasma may produce visible light. An arc discharge is characterized by a lower voltage than a glow discharge, and it relies on thermionic emission of electrons from the electrodes supporting the arc. An arc between two electrodes can be initiated by ionization and glow discharge, as the current through the electrodes is increased. The breakdown voltage of the electrode gap is a function of the pressure, the distance between electrodes and the type of gas surrounding the electrodes. When an arc starts, its terminal voltage is much less than a glow discharge, and current is higher. An arc in gases near atmospheric pressure is characterized by visible light emission, high current density, and high temperature. NORYL resins are a rare example of a homogeneous mixture of two polymers. Most polymers are incompatible with one another, so tend to produce separate phases when mixed. The two polymers compatibility in NORYL resins is due to the presence of a benzene ring in the repeat units of both chains. The goal was to determine why there was electrical arcing on these lighting tracks.
Gideon Analytical Laboratories conducted failure analysis on these lighting tracks in our typical, structured, and proven method. The arcing spot on the bus rail was severely damaged; a sample was taken and SEM-EDS analysis performed. It was not just the power rail, but the neutral bar was affected as well. There was corrosion on the neutral bar. SEM-EDS analysis revealed the presence of chlorides. There are many answers to this problem.
Gideon Analytical Laboratories has been on a winning streak since its foundation in the 1990s. Our knowledgeable and friendly staff have the expertise and the motivation to solve any problem with electrical components. Time and time again, we have come to the rescue of desperate companies looking for answers. We are the light at the end of the tunnel. We are your security blanket. Imagine the peace of mind you will have if you know why your devices are failing. You can fix them. You can save time and money. You can save face. You can build a better business. We can help you do it. Give Gideon Analytical Laboratories a call today.