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Boyan Silyavski
03-06-2015, 10:27 AM
Hi,

may be a stupid question, but is there any way to wire lj12a3-4-z/ax NPN DC6-36V limit switches using only 3 wire cable where there are 2 wires plus separate shield? A way i mean that will reduce electrical HF interference from plasma cutter for example.

Question comes from my ignorance and having a roll of that cable :hysterical:
so i figured maybe the +-thingy could do some miracle and save me to buy another roll:beer:


http://www.mycncuk.com/attachment.php?attachmentid=15443&stc=1

Robin Hewitt
03-06-2015, 11:10 AM
that will reduce electrical HF interference from plasma cutter for example.


If you want to reduce electrical interference put in a fast diode to VCC to dump any big spikes and look for current rather than voltage. (To look for current stick in an opto isolator) :beer:

Boyan Silyavski
03-06-2015, 11:53 AM
If you want to reduce electrical interference put in a fast diode to VCC to dump any big spikes and look for current rather than voltage. (To look for current stick in an opto isolator) :beer:


OK. But i will need separate power supply for that optocouplers, yes? Now what comes to my mind is that my Galil DMC-2183 & 2 ICM-20105 Opto I/Oboard maybe has that already . later will read again the 300 pages manual

Lee Roberts
03-06-2015, 12:05 PM
I have rolls of cable cheap Sily, dont know what the shipping cost would be to you but i could just send you what you need...

6 and 4 core + shield is what i have, they are 100m rolls.

http://postimg.org/image/sd9hc4fiz/

.Me

Robin Hewitt
03-06-2015, 12:41 PM
If you want to avoid interference I would suggest twisted pair. I have a notion that there is a lot more to getting a signal in to and out from a Faraday cage than I know about :very_drunk:

Boyan Silyavski
03-06-2015, 01:05 PM
Thanks guys!

Lee, will PM you now about the cable.

Jess
03-06-2015, 03:11 PM
A way i mean that will reduce electrical HF interference from plasma cutter for example.
As others have said, twisted pair might help. It's really intended for balanced/differential signals, but you can probably get a fair approximation to a ground plane by connecting half of each of the pairs (eg., the striped wires) to the same ground as the breakout board, and running your signals in the other halves of those pairs.

Also, a ferrite around the cable may help; they're fitted to VGA cables (and the like) to suppress high frequency noise.