| I have had more trouble with 'modern' caps. ... | | Speaking of modern - a capacitor characteristic often overlooked in current | times is the manufacturer specified operating voltage RANGE. Using a cap | well below the marked voltage causes it to do two things; lose capacitance | and also become resistive [ie leaky, but not liquid if you follow me]. | ... product recalls due to acceptance of electro caps of higher | than specified voltage. eg 50V instead of 6V. | | John K.
That reminds me of some advice some 'old timers' use to give me. As opposed to resistors, where you use power ratings 2 to 4x the power actually being dissipated, with electrolytics, you want to run them as close as the max rated voltage as possible. Even occasionally going over the rated voltage, was okay, according to the old guys. You don't see that advice given in modern data sheets. They could have spec'd the caps differently back then. It does make some sense, considering how the dielectric layer is 'formed'. If the applied voltage is too low, then the dielectric layer may degrade. Raising the ESR, initially, but may cause the cap to become leaky (electrons, not goo, but goo may follow). If you look at how electrolytics are made, its pretty amazing that they work at all: http://en.wikipedia.org/wiki/Electrolytic_capacitor Their specs are pretty crappy, compared to other types. All they got going for them is capacitance density. Of course, I still use them. Don't get me started on tantalums ! -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
