I am putting the new electric, phone lines and television cable into a
new addition. I was wondering if the phone line or TV cable touches the
electric wires when they criss cross each other will the electric wire
cause any interferance in either the phone line or TV?
If this can cause interferance, what would be the minimum distance
between those lines to be sure one does not cause a problem with the
There is a lot of urbal legend about this but the short answer is you
won't have a problem with coax or twisted pair. If you have the old
style untwisted phone wire and you ran next to the power for a long
distance you might pick up some hum.
If you think about it, your phone runs next to power lines for miles
... but the wire on the pole is twisted
there are code rules about running low voltage lines along 120 power
lines.to prevent cross connection and shock hazard
interference shouldnt be a issue.
you know things change frequently, like for phone catergory 5e might be
a better choice, and use RG6 low loss for cable and dont bury anything
like boxes or splitters in a cieling you cant reach
As long as they are still in the cable jacket they are separated
according to the NEC. It is when you split the wires out of the cable
jacket, like in a box, that you need additional separation.
There is even one style of Romex that has low voltage and line voltage
in the same cable (type NM-S) but you will have a hard time finding
I think you are referring to situations where people run the low voltage
cables (telephone, computer, door bell, intercom, alarm systems etc.)
through, say, the same holes in joists as the electrical wiring etc,.
So in that case they are alongside, in parallel and in contact with the
insulated electric wires.
Usually doesn't cause a problem but it's not good practice? Separate holes
and separation of at least a few inches is wiser.
Not where I live. The power lines run at the top of the pole, the phone
and cable lines run across the middle.
It also matters whats on the end of the power lines. A noisy appliance
like an old motor could be a problem. But phone lines are really not
that low of a voltage that I would worry about that.
"Then said I, Wisdom [is] better than strength: nevertheless the poor
Here is a reference from the TIE/EIA-570-A Residential Telecommunication
"8.1 3.1 Separation distance from electrical power
Separation of telecommunications cable with respect to electrical power
conductors shall meet applicable electrical codes. Additionally, when
telecommunications cable containing metallic elements (e.g., UTP, coaxial
cable) is placed alongside unshielded electrical power conductors inside
wall space or ceiling space, it shall have a minimum separation of 50.4 mm
Q in) from power wire."
Also your local codes (possibly NEC) may have other requirements. You can
check with your building/electrical inspector or the AHJ (Authority Having
Joe Golan, RCDD
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There is only a few places where the lines cross close enough that I
can't keep them at least a couple of inches apart so I ran one of the
wires through a short section of PVC pipe in those intersections.
We get a lot of statric in our phone lines. I always thought it was the
crappy service lines run to the house but now I am wondering if part of
the problem is where the phone line runs into the house within a few
feet of our electric breaker box.
Noise can also be from the phone service wiring - including 'wet cables'
with old (cloth?) insulation. There are a number of bad pairs in the
underground cable that surfaces behind my garage.
Many installations will have a point where the phone line enters the
house where you can unplug the interior phone wiring and plug in a phone
to test if the problem is inside the house or in the TELCO wiring.
Presumably computer signal cables can pickup noise from running across
flourescents (and other arc-discharge lighting?). Probably to a high
frequency for phone.
Old lines is probably the problem. I did complain a few years ago and
they fixed it but it was back in couple of weeks. I am lucky if I can
sign on the internet at 2600 BPS. They ran new lines in my
Brother-In-Law's neighborhood about 5 miles from me and he can
sometimes get over 40000 BPS. SBC has no plans to upgrade around here
so we can get high speed internet.
Age itself has nothing to do with it. There is still plenty of paper
insulated, lead-sheathed cable from the 1920s & 1930s providing good service.
Deteriorated insulation SOMEWHERE is the cause of the noise on your line.
You should have promptly reported the trouble again. ...and again, if
necessary. Then there's your state's Public Service Commission that will take
your complaint if your carrier won't fix the trouble.
You're paying for good service. It's too bad that things have changed to the
point where you MUST be your own advocate ("squeaky wheel") but it's a fact.
Submit reports until the trouble is fixed.
That's pathetic. :(
New lines have nothing to do with it. CLEAN lines do. They replaced the old
cable because the cost to maintain the old cable finally exceeded the cost of
replacement. The old cable must have been beyond TERRIBLE for that to happen.
Lemme guess: You live in the country. I'll bet your "local" CATV provider is
no where NEAR your home and may never be.
SBC certainly has plans to *EVENTUALLY* offer high-speed internet service in
your area. They are simply deploying first closer to the Central Office (or
remote terminal) than further away.
There is a smaller, unincorporated community in the area I service. They
would LOVE to get DSL. We'll get there eventually. Understandably, it isn't
SOON ENOUGH for them.
Even at the furthest distance from the C.0., you should get dial-up
connections in the 26k range on a good pair. Give 'em hell, Harry.
That's a nice touch. However, doing so probably provides mechanical
protection more than anything else. POTS (Plain Old Telephone Service) lines
are regularly run within CLOSE proximity to power lines with NO ill effect.
Static, if it is on ALL your telephones, is probably caused by a fault in your
telco's facilities, possibly MILES away from your home. You should report the
trouble to your provider so they can fix it. You're paying TOO much for your
service to put up with it.
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