EEVblog Electronics Community Forum
Electronics => Projects, Designs, and Technical Stuff => Topic started by: BravoV on July 17, 2015, 11:05:13 am
-
As my recent purchase on bench adjustable switching psu (Manson SPS-8250) 3-15 Vol 25 Amps.
Just fyi its working fine, nothing wrong with it, and output ripple when loaded @ 20A is within specification.
But seeing the CapXon caps, especially at the main biggest one for the secondary part of the switcher, trickles my nerves :palm:, and when I searched at my caps bin, voila, found a NOS Nippon Chemi-Con cap that have the same value (4700 uF 25 V).
The current CapXon cap is KM series with attached datasheet in this post below, while the replacement cap is NCC KME series (datasheet attached below).
Measured using my Mastech LCR meter on this NCC 4700 uF 25 Volt rated cap :
@120Hz, capacitance : 4580 uF , D : 0.121 , Q : -82.9 degrees
Series resistance (Rs) :
@120 Hz = 0.03 Ohm
@1 KHz = 0.03 Ohm
@10 KHz = 0.028 Ohm
@100 KHz = 0.026 Ohm
The C66 (marked in yellow) that is going to be replaced. (Full complete circuit also attached below)
(https://www.eevblog.com/forum/projects/advise-on-replacing-capxon-caps-at-bench-adj-switching-psu/?action=dlattach;attach=161352;image)
The C66 black CapXon and the brown NCC placed on top of it for diameter comparison, the NCC is fatter by 2 mm. As seen, this cap is placed just about 4 mm from the exhaust fan.
(https://www.eevblog.com/forum/projects/advise-on-replacing-capxon-caps-at-bench-adj-switching-psu/?action=dlattach;attach=161354;image)
Top view (without the fan) at the CapXon cap. Quite tight space in there , but I believe I can work it out with the fatter NCC cap.
(https://www.eevblog.com/forum/projects/advise-on-replacing-capxon-caps-at-bench-adj-switching-psu/?action=dlattach;attach=161356;image)
Question :
Is this NCC cap is suitable as replacement ?
Or any other comments are welcome.
-
I would not worry. If it is within spec you are probably good. I would measure the AC ripple of the DC rail to make sure it is not something crazy and stick a thermocouple on them to see if any of them are getting too hot. Apart from that, never pop open any consumer product or you will see a whole wade range of WTF came up with this company name on these components.
-
As much as it makes my skin crawl to say this but I agree with calexanian :palm:. CrapXon caps are a big sore point for me. If it is working, leave it be. If it starts to get :-BROKE, replace all the CrapXon caps and be done with it.
-
Thanks to Capxon (aka Crapxon), I have couple of quad core/dual core computers, two 32 inch TVs and one 40 inch TV for free recently as people discard them as non working.
Most of the Capxon KM series lasts about 5 years +/- 1 year depending on usage according to the date codes stamped on them. I would estimate that about 40% of the bad caps that I have pulled are Capxon branded.
-
Somebody should do a expo with what consumer equipment uses them, and who uses good companies. Realistically in big quantity prices on these caps are so close that it makes no sense for name brand tv and equipment manufacturers to use crap. There are many cap manufacturers that we would consider not brand name that make good quality product they could be using. Or just charge the customer the extra couple dollars for that 52" big screen and use the panasonics or nichicons, etc etc. Penny pinching at its worst. Would you agree that reducing cost by better system wide integrations (Larger asics reducing chip count, better lower parts count design, miniaturization, etc) are better methods of reducing cost than simply looking for cheaper parts that barley work?
-
Calexanian & others, thanks for the replies and reassuring its ok to use it. :-+
Yeah, usually I used the so called "low impedance" type, for example like NCC caps are those KZ? , KY? or LX? series.
Its just currently I just have the same value cap in my drawer, which happened to be this NCC KME series and it is categorized under "general purpose" cap. Also I don't feel like to purchase just one cap for this replacement task.
For others lower value caps like C67 , C68 and C74 which are CrapXon caps too, they will be replaced with NCC LXZ low impedance n long life caps which I have in stock.
Most of the Capxon KM series lasts about 5 years +/- 1 year depending on usage according to the date codes stamped on them. I would estimate that about 40% of the bad caps that I have pulled are Capxon branded.
Thanks for the info for KM series, noted.
-
Somebody should do a expo with what consumer equipment uses them, and who uses good companies. Realistically in big quantity prices on these caps are so close that it makes no sense for name brand tv and equipment manufacturers to use crap.
Most manufacturers are guilty of using Samwha, Fuhjyyu, CapXon and other Chinese brand caps in at least some of their products. For example, Samsung has multiple LCD/TV product lines famous for their high failure rate mainly due to Samwha WB-series caps, same brand and model line as the dead caps I found in my two LG LCDs.