Hello veterans, thanks to help from you all I have managed to save numerous motherboards, monitors and appliances but Im still trying to improve my technique and have some questions on cap selection.
Current project is a samung 50" plasma set that I bought some replacement caps for one of the larger caps that Im starting to have second thoughts about my purchase.
I have generally used Panasonic FC/FM for my recaps of the smaller caps but with the high voltage none of the usual "good maker/series" caps from the forum are not available. I had a challenge finding a reputable brand in same 30mm footprint that had low ESR and a same/larger RC.
The original cap was a Samwha 270uf/450v. RC=1.62
I picked up some Rubycon VXH series which were the largest RC that digikey had in stock from a reliable brand for the 30mm diameter and 105c.
After seeing the caps I realized the RC of the new caps were ~2/3 the size and was only RC=1.43 (~11% less). Trying to get an idea if I am ok to use these and would like to get tips on my selection thinking to help with future projects.
Some related questions I would appreciate any tips/advice.
o) For the larger caps they dont seem to list ESR in the spec sheet so the only real specs I can see in the spreadsheet for same cap/v/temp is the ripple current. Is there a reason they dont give an ESR, is it basically zero?
o) Cap spec sheets do also list some phase angle specs. Is this some sort of linearity measure and does it ever matter?
o) If the caps dont list ESR then I have been making choice on maker reputation and RC. Does ESR generally correlate with RC? Better caps seem usually larger, lower ESR, and higher RC. But I have seen some series as being advertised as more compact per same specs. I guess for more money a better "secret sauce" can be made or is something else like lifetime compromised. Basically Im trying to get some tips for selection criteria to wing it when the usual good maker/series dont exist.
o) Im wondering if I will be ok with the Rubycons I purchased despite the lower RC. Im hoping the PS maker seemed to stick mosty with the same series/maker caps and might have some over design built in since they only have a single cap in that footprint. Since the caps are +/-20% for the cap value there might be some built in margin and given they are a better brand and likely to deliver on the promised specs.
Appreciate feedback/tips on any of the questions.
Thanks much,
Kumasan.
Current project is a samung 50" plasma set that I bought some replacement caps for one of the larger caps that Im starting to have second thoughts about my purchase.
I have generally used Panasonic FC/FM for my recaps of the smaller caps but with the high voltage none of the usual "good maker/series" caps from the forum are not available. I had a challenge finding a reputable brand in same 30mm footprint that had low ESR and a same/larger RC.
The original cap was a Samwha 270uf/450v. RC=1.62
I picked up some Rubycon VXH series which were the largest RC that digikey had in stock from a reliable brand for the 30mm diameter and 105c.
After seeing the caps I realized the RC of the new caps were ~2/3 the size and was only RC=1.43 (~11% less). Trying to get an idea if I am ok to use these and would like to get tips on my selection thinking to help with future projects.
Some related questions I would appreciate any tips/advice.
o) For the larger caps they dont seem to list ESR in the spec sheet so the only real specs I can see in the spreadsheet for same cap/v/temp is the ripple current. Is there a reason they dont give an ESR, is it basically zero?
o) Cap spec sheets do also list some phase angle specs. Is this some sort of linearity measure and does it ever matter?
o) If the caps dont list ESR then I have been making choice on maker reputation and RC. Does ESR generally correlate with RC? Better caps seem usually larger, lower ESR, and higher RC. But I have seen some series as being advertised as more compact per same specs. I guess for more money a better "secret sauce" can be made or is something else like lifetime compromised. Basically Im trying to get some tips for selection criteria to wing it when the usual good maker/series dont exist.
o) Im wondering if I will be ok with the Rubycons I purchased despite the lower RC. Im hoping the PS maker seemed to stick mosty with the same series/maker caps and might have some over design built in since they only have a single cap in that footprint. Since the caps are +/-20% for the cap value there might be some built in margin and given they are a better brand and likely to deliver on the promised specs.
Appreciate feedback/tips on any of the questions.
Thanks much,
Kumasan.
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