Electrolytic Capacitors – an Electronics Industry Scandal?

For repairing my own devices, I usually scavenge capacitors from an old device.

If I can’t do that, or I want to do a slower, more robust repair then I will buy on ebay. It’s not always easy to know which supplier offers a good balance of cost and quality (including spotting fakes) but it seems to work for me.

I would not be upset if common electrolytic capacitors were excluded from this, especially because appliance manufacturers might not have access to the same economies of scale as an electronic component supplier and therefore might not offer good value anyway.

My 2 cents.

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Hello dear Ugo,
I think the most difficult issue is to find the bad electrolytic capacitor, for this I think that the "Nuova Elettronica "ESR meter project should be useful.
They are generic components, their values are clearly written as number of microfarad, you don’t need a schematic to find if the capacitor is the problem, if you can measure the ESR value.
In TV and other big electronic items they are often in the first circuit to create several voltages, sometimes high voltages, and one important thing is to take care to avoid injures or to damage tools.
Often the bigger problem is to open the device without create damages. After this step Electrolytic Capacitors are the worst component, with a medium lifetime of 10 years, so someone as first step of a repair changes the bigger ones.
I think that the fact that they are economics, essentials and fast-aging are all nice characteristics for a vendor, not for the users.

Have you ever seen this site?

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To weigh in on this topic; electrolytic capacitors are not new and are found in virtually every device that handles mains voltage (possibly very simple devices like blenders and hair driers excluded). They have always had a limited lifespan due to their construction technique (electrolyte liquid in/on a medium, contained in a shell). It’s commonly known for instance, that caps should be replaced in valve amplifiers “every ten years”. In reality this would typically mean refurbishing a 30 year old amp requires a recap; if you come across a 50-60 year old amp, it’s likely been recapped once in the 80s or so.

The above is intended to make 2 points - 1: in typical conditions electrolytics don’t die after 2-3000 hours, they will last 10-20 years happily. 2: it’s part of ordinary maintenance to check capacitors and replace as necessary. We simply don’t tend to see/own electronic devices with a lifespan in decades anymore.

In my opinion the issue is not the capacitors - they’ve been the same for 70+ years, and almost all circuits require them (so changing to another product would impact billions of products). They have standardised sizes, ratings, etc - so should be easy to replace.

The fact that so many devices fail due to bad caps largely points to the fact that devices need to be easier to open and diagnose, and consumers need to be willing to do so. They should be the equivalent of “My car’s headlight isn’t working, I’ll check the bulb and then the fuse”. I don’t think there’s a problem with the design of the components or their use.

The comments on ongoing fallout from the capacitor plague (must be almost 20 years ago and still causing issues!) are very interesting though. Of course it’s in the interests of sustainability to make and use longer-lasting components, but I think we’re stuck with electrolytics as a category.

N.B. tantalum capacitors were more popular in 60s and 70s circuits but have fallen out of favour for reasons mentioned including issues when they fail, consistency of spec over time, and also cost.

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