I have several LED light panels and after about 3 years, they are beginning to flicker and go out. About half of them within a few months of each other.

They are 15w panels and the drivers are also dimmers. The LED driver wires directly to 110v main power and there is a standard electrical dimmer switch on the wall that adjusts (presumably) the voltage going to the drivers.

I have taken apart the driver and there is a 10uf 400v capacitor that is bulging out the top and has some burns near the base.

I would like to replace the capacitors, but I am wondering if a larger voltage or capacitance will work better and give them a longer life?

I assume I can put a larger voltage rating, but I am not clear on how increasing or decreasing the capacitance rating would affect efficiency and lifetime of the overall system.

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    \$\begingroup\$ You won’t gain anything by raising the voltage rating. Increasing the capacitance will probably lower PF, but most likley ok. What you want is long life capacitors. Read the datasheet. Temperature and lifetime is (should be, otherwise don’t buy) listed in the datasheet. \$\endgroup\$ – winny Jun 8 at 22:50
  • \$\begingroup\$ Without the schematic of the driver it's impossible to tell with any certainty. One could guess that the ripple current in the capacitor is too high, but most likely this simply shows that the driver should not be driven by a simple Triac based AC dimmer. \$\endgroup\$ – Jack Creasey Jun 8 at 22:54
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    \$\begingroup\$ The caps should be rated same voltage or high , 105’C minimum and rated for more ripple current than LED’s use with Triac. If not designed to be dimmable, they won’t last as the ESR surge current for a Triac high dV/dt results in very high current’s unless design properly with magnetics. These are most stressful on caps. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jun 8 at 23:09
  • \$\begingroup\$ if you want to alter the PCBs to better remove heat from the capacitors, consider soldering wires along the traces to/from the capacitors. Standard copper foil thickness is 1.4 mils (35 microns) for 1 ounce/foot^2 foil. The thermal resistance is 70 degree Centigrade per watt, per square of foil ---- any size foil square. Chances are the foil traces are LONG AND NARROW, thus have very high thermal resistance. Solder any size wire atop the traces, and expect longer life. \$\endgroup\$ – analogsystemsrf Jun 9 at 2:18

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