Author Topic: Why so few convenient screened cables?  (Read 1359 times)

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Online FaringdonTopic starter

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Why so few convenient screened cables?
« on: July 20, 2021, 10:21:50 am »
Hi,
Why are there so few screened cables with the screen connection coming out as a convenient wire so it can be easily connected into a connector?
We only want up to 1A or even signal level, but little exists offtheshelf
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Online T3sl4co1l

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Re: Why so few convenient screened cables?
« Reply #1 on: July 20, 2021, 10:33:52 am »
Because they do..? -- What kind of screened cable are you looking at?

Usually "screened" (as in, foil shield with "drain" wire) has a bare wire just for that.

Any shielded (e.g. braid) cable will necessarily take more effort to do up.

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Offline Jeroen3

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Re: Why so few convenient screened cables?
« Reply #2 on: July 20, 2021, 10:45:37 am »
Farnell has lots in stock, what do you need?
 
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Offline dmills

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Re: Why so few convenient screened cables?
« Reply #3 on: July 22, 2021, 08:47:46 pm »
Note that some foil shield with drain wire constructions can cause a disturbing amount of common mode to differential mode conversion simply because of the geometry.

Also, usually the pig tail you wind up with in that sort of cable winds up acting as a way to radiate all sorts of hash inside your can (or to pick it up), braided screen cables with a 360 degree termination of the braid are generally far superior (But a pain in the arse to terminate).

What the hell are you doing that a fucking power supply needs this sort of tweakery? I can generally get a pass with just a filtered IEC, and some modest filtering on all the signal lines to take the edge off the edge rate so to speak, my biggest pain point is generally HDMI IO and the 850mumble MHz clock harmonic), but there are ways to skin that.
 
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Online FaringdonTopic starter

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Re: Why so few convenient screened cables?
« Reply #4 on: July 23, 2021, 04:36:07 am »
Quote
What the hell are you doing that a fucking power supply needs this sort of tweakery? I can generally get a pass with just a filtered IEC
Thanks, i think i heard you saying that most of what you do is class I?....ie, inside a metal enclosure?
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Offline dmills

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Re: Why so few convenient screened cables?
« Reply #5 on: July 23, 2021, 09:23:58 am »
Yea, we don't touch class II, generally no point in industrial doings, and convincing yourself (And the test house) that **Everything** is really correct is a bit of a 'mare.
 
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Offline Neomys Sapiens

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Re: Why so few convenient screened cables?
« Reply #6 on: July 23, 2021, 06:58:03 pm »
There is actually a very simple solution to connect a wire to a cable screen. they are called SolderSleeve Shield Terminators.
« Last Edit: July 23, 2021, 07:01:08 pm by Neomys Sapiens »
 
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