[LINK] BPL

[Tom Koltai]

> -----Original Message-----
> From: link-bounces at mailman1.anu.edu.au 
> [mailto:link-bounces at mailman1.anu.edu.au] On Behalf Of 
> Bernard Robertson-Dunn
> Sent: Tuesday, 24 March 2009 4:36 PM
> To: link
> Subject: Re: [LINK] BPL
> 
> 
> stephen at melbpc.org.au wrote:
> 
> > Now the IEEE have just ratified BPL standards, let's you 
> and i simply
> > agree to wait and see what happens to emerging BPL 
> technologies. Yes?
> >   
> Stephen,
> 
> Let me try and lift the fog a little. This is not a dig at you, it's 
> actually quite a complex and confusing subject and the term 
> "Broadband 
> over Powerline" is open to misinterpretation.
> 
> Here is an IEEE report:
> 
> <quote>
> IEEE Approves First Standard for Broadband Over Powerline 
> Hardware 
> http://standards.ieee.org/announcements/pr_broadbandoverpowerl
> inehardware.html
<SNIP>
> BPL provides the ability to send high-speed digital data over 
> the power 
> lines between substations and homes and offices, turning every wall 
> outlet into a portal to the Internet."This standard will give 
> both power 
> utilities and the BPL industry the ability to confidently 
> pursue a BPL 
> installation," says Terrence Burns, Chair of the Broadband over Power 
> Line Standards Working Group, which developed IEEE 1675. "It provides 
> for the protection of and safe operation by utilities 
> personnel, as well 
> as the safety of non-utility workers."IEEE 1675 was sponsored by the 
> Power System Communications Committee of the IEEE Power 
> Engineering Society. </quote>
> 
> What this means is that the IEEE 1675 standard apply to the 
> last part of 
> the mains circuit, after all transformers.
> 
> There is also IEEE 643 a "Guide for Power-Line Carrier 
> Applications" a 
> standard for communication over the transmission line network 
> (above 69kV).
> 
> Note this only applies to the transmission line above 69kV.
> 
> There is no standard that applies to the whole system from 
> transmission 
> line to home socket. The 1675 standard applies to the "last 
> mile". There 
> is quite a gap between the
> transmission line network and the last mile.
> 
> The trials may work but they don't demonstrate a workable 
> system, only a 
> single component.

Correct Bernard and as discussed in this thread - this is basically
based on DC distribution at 50 hz and not AC.

So it will work on the high Tension transmission segment and then again
after the lasdt transformer for the local loop but not inbetween - where
it is chopped from 415V+ (up to 10,000[DC]V) down to 240v AC. So there
needs to be a bridging fibre optic analogue digital analogu loop at each
substation for the BPL to actually work.


Tom


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