If you check the 2015 Elektra Award Shortlist, you’ll find KEMET’s F862 X2 Capacitor in the Passive & Electromechanical Product of the Year. We are looking forward to the event in Lancaster on November 24, 2015. Last year, our F-Tech process for high-reliability tantalum capacitors was a finalist.
Personally, I am excited about the F862 and its recognition. While working as a KEMET Field Application Engineer (FAE), occasionally a customer building smart meters would give me a call. The purpose? Premature failures of an X2 Safety Rated Capacitor. Unfortunately, for the client, rarely was the failure premature. The parts were being subjected to conditions outside of what our qualifications covered and conditions specified in our data sheets. In fact, in most cases, we could have predicted failure within the given time frame for the part in question!
The reason for the issue is why the F862 is so important for these AC-Series applications and why are we excited about being a finalist in the Elektra 2015 awards.
Background on the F862 X2 for Harsh Environments
KEMET has used its extensive knowledge and expertise in the field of capacitor technology to develop F862, a new film capacitor. Layers of polypropylene with a light metalization are wound to provide rated voltages of 310 VAC. With an X2 safety rating, these capacitors are suitable for EMI filters in “Across the Line” applications. They have approvals from ENEC, UL, cUL, and CQC.
With a through-hole design common to X2 capacitors, capacitances up to 4.7µF are available. Additionally, the parts have been qualified with the automotive spec for passive components, AEC-Q200. Some Smart Meter applications use X2 capacitors as a coupling capacitor. Over time, the stresses in this application cause the metallization to ionized. The presence of high humidity accelerates this discharge, shortening the life of the capacitors.
What makes the F862 Different?
By utilizing a new sealing epoxy compound, a new polypropylene film variant, and new metalization techniques the life of X2 capacitors in high-humidity environments has been drastically increased. With the growing usage of Smart Meters throughout the world, the need for a high-capacitance capacitor rated for line-level AC voltages is clear.
Film capacitors were always a favorite choice, but it was difficult to find one with sufficient life. The F862 takes the popular X2 platforms from KEMET and improves nearly every aspect of the capacitor, drastically enhancing the life of the capacitor in high humidity or series-coupling applications. Capacitors that may have only lasted 2-3 years in an application now may be able to achieve life ratings over 15 years.