I know that it a common practice to run LV at least a foot away from HV lines, and cross at 90 degrees. It is more important with some signals (unbalanced audio) than others (speaker level audio). I was just wondering if anyone had an idea how susceptible HDMI is to electrical interference as compared with other cables? Brent?

Thanks,
CJ

CJ:
In Theory.....
The balanced lines of HDMI should not be bothered by 110V.
However this is not always the case.
It is a good idea to use your current "best practices".
When running Cat/5 (or Cat/6), yes keep it away from the romex.

Given that HDMI is a digital signal it's unlikely that 100vac is going to interfere with it at all. It's not like a composite, RF or S-video signal. It's a digital bitstream not a video signal.

wkearney99,
but best practices should be maintained anyway. All digital signals appear to work beautifully and perfectly until they don't work at all. Best practices can help keep them from going off the cliff. And you were completely right to say "unlikely."

So, yeah, theory says it doesn't matter. Now, imagine this: would you run an HDMI cable parallel, in fact attached with tape, to a single wire carrying 440 VAC at 400 Hz with about ten amps flowing through it? That's not two conductors, just one, with the return along a different path. This doesn't occur, but think about it. Theory says it should not be a problem. I bet you wouldn't. And that's just an extension of best practices.

It's like the old joke that ends "we've already determined you're that type of girl. Now we're just negotiating the price."

Would you stake your reputation on this once drywall has went up??

Brent's advice is sound, as usual!!

We have a local competitor who pulls only a conduit to the plasma or projo, then when he install the display, he pulls in the component or HDMI cable along with an extension cord with an end cut off, then puts a new end on and all is well

Electrician has told him not to do this on several occasions and would be happy to locate an outlet for him, but declines the offer and say they have been doing it this way for awhile

crazy ass trunk slammers

I would use the HDMI as one of my conductors for the 120. Neutral could be a good choice.

Yes, but the lights would flicker when you have handshaking issues

HDMI is free from electromagnetic interference (EMI) to a certain extent, but the length it will carry a full bandwidth signal (1080p) will decrease as a function of the total induced electromagnetic field(EMF). if you think your HDMI might pick up significant EMI, you should use baluns and run 2 CAT5 or 1 CAT6, depending on the balun. the shielding and twisted pair construction should do better than an actual HDMI cable when dealing with EMI.
if you opt to use HDMI cables instead of baluns, extron makes highly shielded pro HDMI cables that should do well in a high EMI environment:
[Link: extron.com]

Thanks everybody, I appreciate the information.


Isn't this also against the electric code in most areas? What does the electric inspector say (rhetorical question)?

CJ