MEP EP#196: Foamy Power Factors - Electrolytic Capacitors with KEMET

Episode 200 is Coming Up!

• Question / Answer setup like Episode 100
• Send them via Audio Format to podcast@macrofab.com

Ivan Quiroz

• Over 19 years of electronic design and development experience in different industries ranging from aviation to industrial automation
• His technical expertise surrounds the intrinsic requirements and detailed development of circuits
• In his down time, he likes to develop escape room puzzles, sensors, and anything he can 3D print

Suzana Jankuloska

• Is an electrical engineer from Macedonia
• Has been with KEMET for 7 years and as a Product Manager of Electrolytic Capacitors for 3 years
• Loves solving problems and sudoku and is a fan of martial arts and the movie Ip Man

Electrolytic Capacitors

• Discuss ESR, ESL, Dissipation factor, Tan Delta, Ripple current, and life span
• How to read the datasheet for an electrolytic capacitor beyond the value/voltage/dimensions
  • impedance at a known switching frequency
• Brief introduction to a new type of electrolytic capacitor (polymer)
• Link the electrolytic capacitor to the need for a bank capacitors
• Signals through electrolytics
• Leave on forever vs. multiple inrush cycles preferred for lifetime?
• What drifts out of spec first?
• The wear-out failure mode is loss of electrolyte
  • It is possible to measure this by weighing the capacitor before and after operating it at elevated temperature
  • When the capacitor loses a certain amount of weight, it is likely to fail
  • In the old days, the rule of thumb was to predict failure at 50% of the initial weight
• What's the point of those orange SMD tantalum capacitors?
• On large screw terminal caps, are the screws themselves typically intended to carry current, or just to mechanically tie the cap to the mounting surface (bus bar, PCB, etc.)?
  • Is it important to use aluminum screws to match materials to avoid corrosion from dissimilar metals in high current applications?