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Acceptable 'Snubber' Cap(s) for Kenwood KA-7100

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Looks like nice long leads if reading specs right on the Wurth Elektronik metalized polypropylene film safety capacitors. I looked at the datasheet and then noticed also there it is right there in the summary description 20mm leads.

Edit: I'll shrink-tube the leads and leave the capacitor body open to air and plan on going with spec 0.01uF. Thanks!
 
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What do you mean with: "What is the designed failure mode do you know?"?
With the value of 0.01uF (X2 type), choose one with a rated voltage > of your power line, and with the right dimensions to fit over your switch, and with long leads, to easier the soldering. Good safety practise to cover the leads.:thumbsup:
 
Ha. Sorry. Here is translation. If the device fails, can it short to chassis or is it designed to fail open.

It looks like accepted practice here in the U.S. among old audio repair enthusiasts has been a "X1Y2 rated cap."

The Wurth I think is Class X2 (Class Y2/X2). I wonder whether, for this application, these classifications are the same.

I also see now that -- in the Kenwood KA-7100 -- there is a second "snubber." This second one is placed across the terminals of one of the "switched outlets" on the back panel of the machine. Both are on the schematic. I'm not sure what the idea of the second one is. I'd say remove it and consider whether to also replace with a "safety cap" or simply leave it off.

See posts #19-20 in below thread "Confused About the Death Cap" and link to a capacitor of this aforementioned X1/Y2 kind.

81-DE2E3SA103MA3BY2F
https://www.mouser.com/ProductDetail/Murata-Electronics/DE2E3SA103MA3BY02F?qs=sGAEpiMZZMu3dWSqd4Tl0G9pZNen5IS9XSJFyJCTKOY%2BJBWZUiLQ3Q==

https://audiokarma.org/forums/index.php?threads/confused-about-the-death-cap.547287/
 
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Let's see C1: it is mounted on the switch, in parallel to the switch contacts. It is used to suppress arc forming (at turn on/off) between the contacts, therefore to preserve the switch. An X2 film cap is fine here, in case it fails short the switch will simply not work. I would not use a ceramic type here, simply because ceramics are not self healing, like PP are.
C2: this cap is connected in parallel to neutral and hot, and it's purpose is to filter RFI. X2 type is right here, film type as above. I would change it in your KA7100.
Y2 caps are more stringent in specs, mainly they support higher spikes voltages, compared to X2: you can use Y2, if you like.
Some caps are rated both X/Y, since Y type is superior in specs to X.
Now about when it fails, it short or open? From my experience, an X type caps can fail short: it simply made the main fuse to blow. Since it's connected between neutral and hot, no danger to touch the chassis. Y type? I don't know, I never found it out: I think it can fail short or open, like the X, but has higher specs to not fail. If you know more, please share with us.
 
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avionic said:
Why ? Is it broken ?
Click to expand...

Saw replacement on parts lists of others with more experience who have done restorations on this model.

I don't think it's broken. Switch seems to be fine, as well. This amplifier does not look to me like it has seen a lot of wear.

What would you do?

Edit: project is full recap with a few upgrades on a working machine I plan on keeping and putting into my active rotation.
 
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Just a note here that more often than not I use the switch on a power bar to turn on my gear in-part to save gear power switches from wear.
 
Whilst in there recording voltages pre-recap this morning, I took this picture of the snubber for the good of the cause. Looks actually like a quite nice one. Same is across terminals of one of the switched outlets on the back panel as aforementioned. Thanks again all.

Kenwood KA-7100 Snubber.jpg
 
claneg said:
From my experience, an X type caps can fail short: it simply made the main fuse to blow. Since it's connected between neutral and hot, no danger to touch the chassis. Y type? I don't know, I never found it out: I think it can fail short or open, like the X, but has higher specs to not fail. If you know more, please share with us.
Click to expand...
My understanding is the X types are to be used across the line, and Y types are to be used from line to ground. My instincts about this are that the Y types will be made much more robust (than X type) because their intended use is more demanding.
 
Hyperion said:
My understanding is the X types are to be used across the line, and Y types are to be used from line to ground. My instincts about this are that the Y types will be made much more robust (than X type) because their intended use is more demanding.
Click to expand...

Yup, I agree with you.
 
Spenser said:
Pricey:

539-104M06QC100
https://www.mouser.com/ProductDetail/Cornell-Dubilier-CDE/104M06QC100?qs=/ha2pyFaduhC77umFSbNCmtPClivAhZ14/CHPIu2kLFC75TzrWfAMw==
Click to expand...

Of the caps listed in this thread, this is the only one that is an arc-suppressing snubber array, designed to be used in parallel with switch contacts. Use this one to help preserve your power switch. X caps go across the line to suppress RFI/EMI, Y caps go from line to chassis for the same purpose. X caps are designed to fail shorted and pop a fuse. Y caps are designed to fail open so as not to create a shock hazard.
 
tarior said:
Of the caps listed in this thread, this is the only one that is an arc-suppressing snubber array, designed to be used in parallel with switch contacts. Use this one to help preserve your power switch. X caps go across the line to suppress RFI/EMI, Y caps go from line to chassis for the same purpose. X caps are designed to fail shorted and pop a fuse. Y caps are designed to fail open so as not to create a shock hazard.
Click to expand...

So the original C1, which is just a cap (no resistor in series) is used for which purpose?
 
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