[mythtvnz] OT: Recommended wiring scheme and RJ-45 connectors for Lexcom (Cat7) cable

[James Gray]

On Tue, Feb 16, 2010 at 6:51 PM, Jean-Yves Avenard <jyavenard at gmail.com> wrote:
> Hi
>
> On 16 February 2010 16:34, James Gray <james6.0 at gmail.com> wrote:
>> To install anything with voltage greater than that considered to be
>> SELV (safe extra low voltage), you must be a registered electrician.
>> This is basically any time of signal or telecomms cabling (ELV in this
>> context, means anything lower than 100V AC, or 150V DC. 240V is
>> actually considered low voltage, compared to a 10,000V power line it
>> is anyway)
> Hum..
>
> Anything below 1000V AC and < 1500V DC is considered low voltage under
> the AS/NZ cabling rule.
>
> Knowing that a standard POTS is 50V DC and up to 90V AC ; that makes
> it only a sparkie can work on telecomm cable according to your post
> (don't know what the deal is in NZ)

I am a Telecommunications technician. I work in New Zealand. I work
with telephone installations on a regular basis...

You actually have an interesting point there... Reading further into
it, Extra Low Voltage is defined as <120V DC or <50V AC... Hence a
ringing telephone line would be considered low voltage at 90V AC

In practice it's never been a problem. Telecom's PTC documents make
reference to the fact that many of their own linesmen (well, telecom's
chorus's transfield's/downer's lines people) are not registered
electricians, so phone jacks should not be installed within electrical
installations which require a registered electrician to work on..