angelaudio
Super Member
Yes I meant fish paper. My mistake
My Sansui 1000A Restoration
- Thread starter angelaudio
- Start date
When I said "value," I was referring to the capacitance (uF). The cap in the photo is 330uF. Compared to the 200uF original, it will draw more peak current, especially when first powered up. That's why I suggested larger capacity 3A rectifier diodes. About the voltage rating, 350V each is plenty to safely accommodate modern line voltage in the 1000A. 400V is also OK.
Jack
angelaudio
Super Member
The screw technique worked great Cap!
Thanks a bunch! I used a grinder to level off the bottom and now all I have to do is take the remaining foil and rubbery gunk out from inside. After it’s cleaned out and ready for the re-stuff would hot glue from a glue gun be appropriate as a way to hold it inside? Since the top of the cap won’t be exposed I was thinking of just putting some hot glue on the inside top of the can and putting the capacitor in there and then putting some hot glue around the edges in between the can and the cap.
I would use electronic grade silicone if I needed glue.
https://www.amazon.com/gp/product/B0063U2RT8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0063U2RT8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
angelaudio
Super Member
I noticed one of my multi section cans has two voltage ratings, “SV 575 VDC” & “WV 500 VDC”
While my new CE can is only rated at 525 VDC.
Is this cause for concern? What does “SV” indicate? Can I safely use the 525V CE can in it’s place?
While my new CE can is only rated at 525 VDC.
Is this cause for concern? What does “SV” indicate? Can I safely use the 525V CE can in it’s place?
"W.V." is working voltage. "S.V." is surge voltage. You need to determine the surge voltage rating of the CE cap. I wouldn't want less than the original.
I use that too, but be warned, it's more like paste than the usual RTV. Dow 3140 is much easier to work with, but also much more expensive. Above all, don't use the standard RTV that smells like vinegar. The acetic acid corrodes copper and other metals.
Jack
angelaudio
Super Member
Checked antique electronic supply and the SV is not provided. Might have to email them.
I would contact CE manufacturing directly with the capacitor model number. I don't have any experience with their company, but maybe they'll be willing to help, rather than forcing you back to the retailer.
https://www.cemfg.com/contact
https://www.cemfg.com/contact
angelaudio
Super Member
I forgot to buy insulators for my can caps. Can I use fish paper for this purpose and cut something similar to this?
Fish paper isn't strong enough. I know it's a pain, but I would order the insulators after you determine whether different caps will also be needed. Incidentally, I've bought a fair amount of building supplies from AES. Some of their PVC wire is really good, highly resistant to soldering heat and impossible to find anywhere else. Just a good, all-around supplier for a lot of tube-specific items.
Jack
capbeefheart
Active Member
Most modern caps don't include surge voltage ratings written directly on them but are typically in the datasheet. The way I understand it is they run the surge voltage for 30 seconds every 5 minutes and repeat that 1000 times. That was the last industry standard I read but there may be other standard tests slightly different. I think you will find most modern caps will have a surge voltage rating of ~120%-130%.
I hope you have better luck with the CE manufacturing multi-section cans, I had to stop using them as I had too many come back after a short period with dead sections. Others have reported the same thing so i just no longer trust them. With the fact that they are so expensive from any company that makes them I just stuff them since it's pretty easy to do and I know for certain I have a quality capacitor installed. You can't even find datasheets from CE or others that make them.
Glad you got the guts out with the screw, it always worked well for me but if you didn't use heat (you said it was tough coming out) then next time you want to use a heat gun to warm up the tar inside and the guts just slide right out. Heat also makes it easier to get the rest of the goop out from inside after you pulled the sections out.
I hope you have better luck with the CE manufacturing multi-section cans, I had to stop using them as I had too many come back after a short period with dead sections. Others have reported the same thing so i just no longer trust them. With the fact that they are so expensive from any company that makes them I just stuff them since it's pretty easy to do and I know for certain I have a quality capacitor installed. You can't even find datasheets from CE or others that make them.
Glad you got the guts out with the screw, it always worked well for me but if you didn't use heat (you said it was tough coming out) then next time you want to use a heat gun to warm up the tar inside and the guts just slide right out. Heat also makes it easier to get the rest of the goop out from inside after you pulled the sections out.
capbeefheart
Active Member
In regard to going bigger with capacitance.
Someone mentioned the rectifiers and yes they need to be able to handle the repetitive peak forward current. The more capacitance the more current is needed every 8mS charge cycle to charge the capacitance.
What wasn't mentioned was transformer winding heat issues. Often manufacturers do not go overkill and size the transformer accordingly to their circuit. You start adding too much capacitance the winding needs to deliver that extra current to charge up that extra capacitance and can stress the transformer.
Someone mentioned the rectifiers and yes they need to be able to handle the repetitive peak forward current. The more capacitance the more current is needed every 8mS charge cycle to charge the capacitance.
What wasn't mentioned was transformer winding heat issues. Often manufacturers do not go overkill and size the transformer accordingly to their circuit. You start adding too much capacitance the winding needs to deliver that extra current to charge up that extra capacitance and can stress the transformer.
angelaudio
Super Member
That worries me. The capacitance is almost double what the original circuit calls for. I’m leaning towards just getting the original value in that case.My local tech used to tell me add more capacitance in “X” location and you’ll get more bass, etc. but I did wonder whether altering the values stressed a part of the circuit, now you’ve confirmed my suspicions. Thanks Cap
angelaudio
Super Member
@capbeefheart
While we’re on the topic, how does the additional 4 or so volts (120v VS 117v) from the wall socket affect the circuit? What is that additional voltage altering or stressing, if anything at all? Would a thermistor then be the best solution as opposed to upping filter capacitor values?
While we’re on the topic, how does the additional 4 or so volts (120v VS 117v) from the wall socket affect the circuit? What is that additional voltage altering or stressing, if anything at all? Would a thermistor then be the best solution as opposed to upping filter capacitor values?
You're lucky if it's only 120V. My home mains are frequently 125V -128V, and I'm considering adding a bucking transformer to the entire audio system. About the caps, Jim McShane's rebuild kit for my Citation V included caps that are much larger than the factory values. I can't promise it's safe to do this in the 1000A, but I haven't heard any reports of Citation transformer failures after making this change.
Jack
angelaudio
Super Member
Wow that’s pretty high. Mine run about 121.5ish. Haven’t noticed any increase in heat radiating from the Citation V?
Keep in mind that the power transformer heating due to the higher peak currents will be a problem, too, and there's no real fix for that outside of going with a larger transformer.