|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
128.125.179.205
In Reply to: RE: Motor run capacitors revisited posted by Michael Samra on May 04, 2017 at 17:57:20
The idea of small capacitors in a power supply is just not appealing to me. There are good things about motor runs - few other types compare to them in low ESR and high current capability. Many have ratings in thousands of volt-amperes. Take in your hand and feel the thing, as Ukrainian proverb says.
Follow Ups:
I don't disagree with you.I love film caps in the power supply but sometimes room constraints only permit use of lytics.The new poly film caps of high of capacitance are very good.They have made them smaller but still much larger than a lytic in capacitance comparison. Take a look at the caps I put here for comparison.Here is a 51uf Solen at 630vdc and a 370vac MR good to 700vdc and the 50uf@500v Panasonic. Notice the difference in physical size but you can get CDE film caps and Wimas that are 600vdc to 900vdc that are smaller as well.
100uf MR cap,100uf at 630vdc Solen film cap and 100@500v Pannasonic film cap.While the voltage rating of the MR is 370vac,it is good to 700vdc at least because of the oil.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken
Edits: 05/05/17
In most cases, you cannot fit these big cans into an existing design, where DC Links and other compact caps may be quite handy. DC links don't have the current capability of motor runs, but they have pretty good loss factor at 10 kHz and thus not restricted to 50-60 Hz operation.
so dc link not suitable for powersupply?
or should using for first cap be avoided?
Exactly
So many people look at 50-60 Hz operation labeling on the cap and think that is what the cap is limited to and it's just not true.They put this rating on to designate it for non rectified appliance applications as that's what they are mostly used for. They often call big 12v batteries automotive batteries but that doesn't mean they can only be used in automotive applications but that is what their intended use is.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: