Need help finding this capacitor.

jpanhalt

Joined Jan 18, 2008
10,234
Why do you need 400V if the one being replaced is 200V?

In the photos, it looks like two of the pins are connected to the same terminal of the capacitor. Is that the case?
 

Thread Starter

apache2223

Joined Dec 5, 2019
35
Why do you need 400V if the one being replaced is 200V?

In the photos, it looks like two of the pins are connected to the same terminal of the capacitor. Is that the case?
I do not need 400v, that is the one suggested to me by peterdeco. Yes, both are connected to same terminal on cap. But it's hard to tell if both pins are connected to same trace on the board because of the silicon covering.
 

jpanhalt

Joined Jan 18, 2008
10,234
You can usually go up in voltage rating but not down when replacing a capacitor. Sorry, I misread your earlier response.

Dimensions would help. There are 3-terminal capacitors. What you are looking for is an ordinary 2-terminal capacitor that is brought out to 3 or (more likely) 4 pins. What does the resistance between the two pads that are connected at the capacitor read?

http://jianghai-europe.com/wp-content/uploads/JE16_CD_294_BW.pdf
Note that 3 of the 4 pins are connected together. Just use 2 of them, assuming the polarity is correct..

1598873069242.png
 
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Thread Starter

apache2223

Joined Dec 5, 2019
35
You can usually go up in voltage rating but not down when replacing a capacitor. Sorry, I misread your earlier response.

Dimensions would help. There are 3-terminal capacitors. What you are looking for is an ordinary 2-terminal capacitor that is brought out to 3 or (more likely) 4 pins. What does the resistance between the two pads that are connected at the capacitor read?

http://jianghai-europe.com/wp-content/uploads/JE16_CD_294_BW.pdf
Note that 3 of the 4 pins are connected together. Just use 2 of them, assuming the polarity is correct..

View attachment 216030
Dimensions are 45mm x 32mm. They can be a few mm taller, but no wider than 32mm. Spacing is 10mm between the main pins and 6mm between the pins on same terminal. I'm curious, why fid you say more likely 4 pins? These were the factory installed caps and they have just the 3 pins. Thanks btw for the help, much appreciated!
 

jpanhalt

Joined Jan 18, 2008
10,234
Dimensions are 45mm x 32mm. They can be a few mm taller, but no wider than 32mm. Spacing is 10mm between the main pins and 6mm between the pins on same terminal. I'm curious, why fid you say more likely 4 pins?
Because that is what I have seen on DigiKey and other distributot sites. Just personal experience. For example:

1598874984028.png1598875046420.png
Those are from Rubicon and Vishay datasheets respectively. There are also 5-pin versions. That type of capacitor is often large and heavy. Thus, additional pins are present for mechanical reasons.

Epcos (https://media.digikey.com/pdf/Data Sheets/Epcos PDFs/B43540_Rev_Dec_2013.pdf ) makes a 3-lead version that looks like two pins on the negative pole and only one on the positive pole:
1598875486472.png
 

Thread Starter

apache2223

Joined Dec 5, 2019
35
I did find that one (Epcos Brand) and a few others like it, but the spacing was a bit short (4.75mm) between the pins on same terminal. 6mm is minimum spacing. I was told just to use a 2-pin cap, do you think that would be OK? Also, the old caps weigh about 26 grams, is that considered heavy. They feel very light. Thanks again!
 

jpanhalt

Joined Jan 18, 2008
10,234
That's why I asked whether the two pads that connect to the shorted pins are connected elsewhere. If they aren't, you could still put a wire in one and connect that to the other.
 

Thread Starter

apache2223

Joined Dec 5, 2019
35
That's why I asked whether the two pads that connect to the shorted pins are connected elsewhere. If they aren't, you could still put a wire in one and connect that to the other.
You'll have to forgive me. I'm pretty good at soldering, but I'm learning about electronic circuits still. By connected elsewhere, what do you mean? I can't see on the board because if that covering. It looks like the 2 pibs on same terminal go to the same trace on biard, but I'm not sure.
 

Thread Starter

apache2223

Joined Dec 5, 2019
35
That's why I asked whether the two pads that connect to the shorted pins are connected elsewhere. If they aren't, you could still put a wire in one and connect that to the other.
Also, why would they bother with that 3rd pin if it just goes to the same place as the pin it's attached to?
 

jpanhalt

Joined Jan 18, 2008
10,234
Also, why would they bother with that 3rd pin if it just goes to the same place as the pin it's attached to?
As I already mentioned, additional pins may be for support. Notice that the arrangements are not symmetrical, so I suspect another reason is to prevent wrong orientation during assembly. The black strip is often used for orientation, but using the pin arrangement is foolproof.
 

Thread Starter

apache2223

Joined Dec 5, 2019
35
Ahh, OK. Where you said "Thus, additional pins are present for mechanical reasons." I wasn't sure what that meant and forgot to ask. I'm also trying to install a back cover on an iPhone 11, so forgive me for my ignorance at this time. So what would you suggest I do? I can't find a schematic and can't see where the pins are connected, so could I make a pin ot of nickel or something and try to solder it to the terminal that has the 2 pins connected to it and run it up to where the 2nd pin would connect on the board? That is if I buy one with just 2 terminals? And I will measure the resistance between the 2 pads as soon as I can.
 

jpanhalt

Joined Jan 18, 2008
10,234
Do you have a multimeter that can measure resistance? Use that to test whether they are connected. If not, you can usually see the traces in good light. They are covered with what's called "solder mask" that can be any color. Green is common. I would trust my eyes and carefully look at the board more than a multimeter.
 

Thread Starter

apache2223

Joined Dec 5, 2019
35
Do you have a multimeter that can measure resistance? Use that to test whether they are connected. If not, you can usually see the traces in good light. They are covered with what's called "solder mask" that can be any color. Green is common. I would trust my eyes and carefully look at the board more than a multimeter.
There is no resistance when measuring between the 2 pins connected to same terminal. I attache 2 pics of the board so you can see what I am seeing. When I was removing the caps, I didn't know they had 3 pins, so I couldn't figure out why they weren't coming out. I messed up the board a little and will have to fix it. But it's hard to see with that covering of silicone or whatever it is on the board.
 

Attachments

jpanhalt

Joined Jan 18, 2008
10,234
This (red arrow) is the trace:

1598887249011.png

If the capacitor fits between the bottom hole in this picture and the hole not shown, I 'd be sure there was continuity with the trace. Repair of where it is messed up may be difficult. You might need to scrape off the solder mask over the trace and solder a wire to it.

Curious, why did you decide to replace both capacitors?
 

MaxHeadRoom

Joined Jul 18, 2013
21,426
You are aware that start capacitors above 20 µF are always non-polarized aluminium electrolytic caps?
They are non solid electrolyte and therefore they are only used for the short motor starting time.
Any AC motor start & run capacitors should always be Motor start rated.
Max.
 

Thread Starter

apache2223

Joined Dec 5, 2019
35
You are aware that start capacitors above 20 µF are always non-polarized aluminium electrolytic caps?
They are non solid electrolyte and therefore they are only used for the short motor starting time.
Any AC motor start & run capacitors should always be Motor start rated.
Max.
Yes, I was looking only at aluminum electrolytic caps. Where in the specs does it say if it is motor start rated?
 
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