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My dad recently got his hands on an old Canon P-8 Cinestar S projector. When he turned it on he forgot to turn the switch at the bottom to the correct setting so it gave a bang and smoke came out. We checked and it was set to 160V instead of the 240V we have in Europe.

After opening it up I saw that a capacitor had popped and a fuse had blown, but besides that it looks ok to me. The problem is that I can't make out what exactly the specifications of the cap are, I have some information but the "wrapper" got torn up so I might be missing something. The parts that I can still make out read:

  • 026602A (I'm guessing this is the product nummber but there's a tear after the final 2, the A is from another part)
  • Nippon Chemi-con
  • OIL
  • .1(k) 400V
  • CP-C

I checked on google and found one photo of this thing opened up (You can see it at https://van-eck.net/en/spare-part-finder/?cat=film&merk=28&type=P8%20Cinestar%20S) it's the capacitor on the bottom right of the photo.

Looking at similar questions on here I found that apparently I can replace it with a higher voltage capacitor, as long as it's the same farad rating, the problem is that from the information I have I don't see an obvious farad rating. There's just the .1(k), but while I don't know a whole lot about electronics I know enough that capacitors are usually measured in uF of nF, but definitely not in kF.

I was hoping that someone could help me figure out what I can replace it with. The user manual I found online says the fuse is a 2A 5x20mm fuse, so that's easy to replace.

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    \$\begingroup\$ You have to know what else received overvoltage and might be fried now. Just because one capacitor exploded and a fuse blew, and nothing else looks like damaged, there can be damage all over the place. \$\endgroup\$
    – Justme
    Commented May 22, 2022 at 13:25
  • \$\begingroup\$ @Justme and the simplest and easiest way to find out is practically to replace the cap and the fuse and try it out. \$\endgroup\$
    – Sim Son
    Commented May 22, 2022 at 19:01

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About the capacitor and pictures in the link, I did this collage, highlighting the C1 you mentioned in the lower right side. I also saw another Capacitor - an Electrolytic one, inserting a zoomed view in the lower left of collage.

enter image description here

From the Right zoom, it seems the capacitor is a simple Snubber capacitor between brush contacts of an universal motor. The value 0.1K is measured in picoFarad (pF) só originally it means 100 pF. However, most circuits to minimize interference of AC brushed motors use higher capacitance values as 1000~2000pF (1nF 2nF) and here you can see the Snubber influence to reduce inductive overshoots using an RC (1500pF + 27R).

See also this illustration and compare with your wirings:

enter image description here

(Image source: Blue Point Engineering - R-C Snubber Noise and Arc Suppressor)

About C1, original value is 100pF, but I would use 1000pF (1nF) with a 600V to 1KV rating, ceramic or film; or use a EMI Suppression Safety Capacitor class X1 400V, same 1nF, as here.

Another point of attention might be that electrolytic (left side): I would replace it, as most electrolytic capacitors age and dry. If exposed to an overvoltage, then it may be further damaged and should be preventively replaced.
You could replace it for a New 47uF x 400V. Tip: use a permanent marker (or check the photo) to confirm the correct assembly polarity.

An old device like this one is mostly mechanical & electrical, with a minimum of electronic parts, so you may be lucky and the 150% of overvoltage (240/160) did not cause further damage.
I wish you luck and I would appreciate to know how the repair & fix worked.

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