I have two electrolytic capacitors [ Sprague Powerlytic / 36DX / 95°C / 9800uF / 100VDC / 0905L 25 ] that I had shipped to me on 01-29-10 from Allied Electronics. They have never been used [powered up], and have been well taken care of in terms of temperature storage. They are replacement caps for the power supply block of a audio power amplifier, as the current ones are very leaky. My question is: In all that I have read, as long as electrolytic capacitors have never been powered up, they have a fairly long shelf life. Does anyone have information contrary to this?? Thank you in advance for your time & consideration.
-
-
Re: Unused/New Electrolytic Shelf life
There is no problem, especially with those big filter caps intended for audio amplifiers. If they were sitting for 5-10 years maybe you would have needed them reformed (variable voltage source, series resistor, series amp meter), watching the leakage current as you slowly advance the voltage towards their rated value. But for just a couple years they should be okay and require no preparation.A working TV? How boring!Originally posted by PeteS in CA -
Re: Unused/New Electrolytic Shelf life
Where have you read that not powering them up improves shelf life? From recollection, that's the worst case as never powering them up would cause the most oxide loss on the foil. Regardless I agree with Th3 uN1Qu3, the caps should be fine for the application.Comment
-
Re: Unused/New Electrolytic Shelf life
@ 999999999 + @ Th3_uN1Qu3:
Thank you gentlemen, for your dedication to a resolution. I thoroughly appreciate your efforts. As far as where I read that "not powering up will increase shelf life", it was 2+yrs back when I purchased them, and another 1-2 years back added to that in finding the information[??] that I used to make the purchase decision. I cannot remember the "source" of the info that stance came from. After re-investigating the issue, it appears you are correct, although, some manufacturers have trouble remaining "crystal" in their statements. Should [either] you want a good read, as well as some additional knowledge, visit: http://my.execpc.com/~endlr/electrolytic.html . It is a site, "chock full of nuts", as the saying goes. In any event, I thank you for "setting me straight", as it were, and prodding me to do some additional research on my own. Kudos to you [both], and again, Thank you. ---SamComment
-
do capacitors have a limited life even if just kept in a box in storage? -
This is my first attempt at troubleshooting a board like this, I know I could just buy a new board but I'm curious to figure out how this works. I've been testing different components in the evenings this week and I think the problem is with the IC failing to start up for some reason. When the board is plugged in there is no standby voltage.
Then today it randomly sprung to life like a zombie but shortly died thereafter. I have no idea why it would have done that and its the first time I've seen it running. I discharged capacitors on the board last night, then it was sitting today.... -
Hi.
I have a laptop Dell Vostro 3501 which did not POST. When connected to power supply and turn it on, the keyboard backlight would turn on but nothing else. Sometimes there was 1 BEEP code indicating problems with BIOS.
Then I disassembled it to read the BIOS chips. It had 2 - 64mbit and 128mbit. I connected CH341A (with 3.3v mod) to both of the chips (still soldered on main board) and read them.
After I reassembled laptop back and tried to turn it on. Now there is no sign of life. Not even keyboard backlight.
Then I took the motherboard out... -
From what I've found, the endurance of a liquid electrolytic cap is determined by the loss of electrolyte. If a cap is rated for 1000 hours. That's typically for a straight run test. How would the life vary if the cap is intermittently heated to its rated temperature (105C). Maybe for an hour at a time then cooled back to 30-40C (just a random number). Would the life still be 1000 hours?
Does it make a difference in the life expectancy if the cap is heating from ripple current (internal heating) instead of from the external ambient temperature?
Why do polymer capacitors... -
Hello,
can I use this cap:
https://www.tme.eu/en/details/ues1h4...tors/nichicon/
Capacitor: electrolytic; bipolar; THT; 47uF; 50V
to replace this capacitor: Electrolytic Radial E 47uF/50V 6.3x11 RM2.5 105°C Jamicon
What exactly I can expect to install bipolar electrolytic cap instead a regular one?
Thanks.
Comment