Polarity of european screw in Electrolytics?

[Twist Turner]

After 20 years of this Schoeps CM640 tube mic laying around I decided to get it up and running again as it did run when i first got it. I opened the power supply and all 4 capacitors are leaking badly so they need to be replaced. My problem is, only one is marked with Polarity. It has a + stamped on the lead from the cap, the rest have no markings what so ever as far as polarity. Is there a known method to determine this? Some of them have a black dot where it comes out of the cap, does this designate - ? Sorry if these are really basic questions but i've never dealt with these old screw in Eurocaps before.

 

[abbey road d enfer]

The high voltage caps have their negaticve connected together to ground. The low voltage ones have their positive connected together and also to ground.
That should be enough to determine where they are.

 

[Twist Turner]

I took one out and the pins are marked 1 and 2(numbers were hidden behind wiring), was there a European standard for these? Like 1 = Positive, 2 = negative? I can't find anything on the internet and i really don't want to have exploding capacitors, i've experienced that before and it's no fun

 

[Khron]

No chance of determining that from where and how they're connected in circuit?

 

[Twist Turner]

no you would think all the negatives go to ground but that's not the case

 

[Khron]

I meant more like reverse engineering the circuit. I doubt it could be anything overly complex...

 

[abbey road d enfer]

no you would think all the negatives go to ground but that's not the case

I alrady explained earlier how to identify the connections. It should just take a multimeter.

 

[Whoops]

After 20 years of this Schoeps CM640 tube mic laying around I decided to get it up and running again as it did run when i first got it. I opened the power supply and all 4 capacitors are leaking badly so they need to be replaced. My problem is, only one is marked with Polarity. It has a + stamped on the lead from the cap, the rest have no markings what so ever as far as polarity. Is there a known method to determine this? Some of them have a black dot where it comes out of the cap, does this designate - ? Sorry if these are really basic questions but i've never dealt with these old screw in Eurocaps before.

Check what Abbey posted...

Also, take photos of the caps and show us...

Search for the schematic for the PSU, that would be pretty easy to figure out with the schematic.
Do you have it?
do some deep google searches or ask schoeps for the schematic mentioning it's for repair only

 

[abbey road d enfer]

do some deep google searches or ask schoeps for the schematic mentioning it's for repair only

I googled it in two strokes...

 

[Whoops]

I googled it in two strokes...

Did you find the PSU schematic?

 

[Twist Turner]

Ok, i figured it out.........and terminals marked #2 are indeed ground, and #1 positive, also the ground has continuity to the metal case. Caps just arrived so i'm digging into this now.

 

[abbey road d enfer]

Did you find the PSU schematic?

Yes. two strokes, as I said.
I googled "schematic schoeps cm640", that lead me there:
https://www.google.com/search?client=firefox-b-d&q=schematic+schoeps+cm640
I picked the 2nd link, that led me there:
https://www.gearslutz.com/board/high-end/190416-schoeps-cm640-power-supply.html
The 2nd post:
Attached files
File Type: zip cm64-640 schoeps.zip

 

[Whoops]

Yes. two strokes, as I said.

Pretty easy then