Originally Posted by Neurorad
I'm under the impression that a shield is only useful if it's grounded, but I really don't know. I also think the shield is to protect from nearby AC, and not the adjacent DC power.
If the connector was grounded, e.g. for STP, the instructions are quite explicit. I'm just not sure of the proper use of a Cresnet drain wire.
AC over DC yes, because alternating is more likely to interfere, but current is also going in the opposite direction from which the data is being sent back to the controller, so i'm not sure in that case. I don't have much information on how they got the specs for Cresnet either. But what I imagine, power sent through Cresnet is to allow powering up a device, in which in turn, sends data back through Y and Z to the controller for it to do something on anything on the OUT, whether that's IR or Serial out, etc...
Although the purpose of shielded cable basically keeps all the electrons in the flow within that shield so that nearby equipment and all that isn't affected if in the case something does happen with electrical shock. This is I believe, usually the reason why a shielded bundle of wires comes with a ground inside, because if you're grounding for any purpose, you'll have to dispose of all that electricity someplace, and to keep it on a good path and not have it affect anything else nearby, that's what that shield does. And you'll see Cat6 and Cresnet included where the ground wire is just stranded wire with no coating if it's shielded.
My father was a Test engineer that did all the electrical work at Nortel when it was at it's high point. He would probably be able to give more answers to me about all this stuff if I was curious enough to ask. I'm not an electrician, just an AV guy
But i'll learn all this stuff eventually. It's good to know, and just because i'm not an electrician doesn't mean I may not need this kind of information.
~AceEdited by AceInfinity - 9/18/12 at 8:26pm