Keep blowing capacitor inside converter

Gordon Three hit it absolutely on the head and he DID cover temps. My apologies SENOR!

Choose 105c. Replace BOTH caps. If you can jam in 500-volt caps do it but that's very doubtful they would fit never mind find them.

Gordon Three has absolutely the correct answer. Unless a person themselves with their own hands diagnosed and themselves repaired converters and power supplies, what are they doing inside a repair thread? My former 400-watt Megawatt now called Hyperwatt. is now a constant duty 650-watt charger with utter success.

The full-wave bridge rectifiers inside these units should have a heat sink and most do not.

The capacitance of all capacitors must remain the same value. But stay away from Chinese landfill. Something Mr. G3 missed is temperature. Stick with 105c units, his list of acceptable brands is impeccable. If a 300 volt or 400-volt capacitor will fit, use it.

If a unit uses a Schottky rectifier rated 80 amps over the original 30 amps and 150 volts PIV over 100 USE THEM.

Converter model?
OEM capacitor specs?
Replacement specs?

If this is a WFCO.... do yourself a favor and get a different brand.

Converters aren't that expensive and they are relatively easy to replace (ie DIY). You might consider just replacing the converter. (lots of thread/youtubes etc). Just my 02.

Welcome to the forums!

The problem has nothing to do with surges.

Something called "ripple voltage" is killing the capacitor. Replace with same uF rating but at voltage rating of 50 VDC or 65 VDC. Make sure you get a capacitor rated for at least 85°C as well, 105°C is better. Nichicon, Panasonic, Murata, Sanyo, some of my favorite brands for such things.

It's a sign your converter is failing, something wrong with the power supply circuit putting out dirty current.