Hit a surprising stat on capacitor failure rates from a trade journal

I was flipping through an old NECA magazine last night and saw something that caught me off guard. They said aluminum electrolytic caps have a 10x higher failure rate in power supplies running above 50C ambient temp. Has anyone else noticed this holding true in their bench work?

2 comments

2 Comments

jessew834d ago

Yeah that lines up with what I've seen on the bench for sure. I've had way more power supplies cook themselves when they're crammed into tight spots with no airflow especially in those cheaper Chinese made units where they skimped on the cap quality. If you're working on something that runs hot for a long time, swapping those electrolytics for some 105C rated ones makes a big difference, but you gotta check the ripple current rating too or they'll still blow early.

blair_gibson784d ago

Wait, is this actually a real study or just anecdotal? I mean, those trade mags sometimes cherry pick data to sell ad space for higher end components. Maybe it's just me but I've pulled apart plenty of old power supplies from the 80s and 90s that ran hot as hell for decades and the caps still measured fine. Could be that other failure modes like bad solder joints or failing fets get blamed on the caps instead. Plus if you're running a quality brand like Nichicon or Panasonic, I've seen them survive way past their rated temp limits without issue. Idk, seems like the real problem is cheap manufacturing more than the cap type itself.