Re: Homeplugs



Dave N wrote:
John Rumm wrote, on 08/04/2010 01:45:
Dave N wrote:
John Rumm wrote, on 07/04/2010 03:11:
Steve Hayes wrote:

The only saving grace is the hope that the PLC signal is going to be
attenuated as it passes from the ring main to the lighting circuits at
the consumer unit but I wouldn't like to count on that.

Having done some experiments on this I can confirm that there is some
attenuation from one circuit to another - but not sufficient to prevent
operation of the homeplug devices. I have established reliable
connections for example through two MCBs, four RCDs, & one HRC fuse
distributed in three consumer units.

That's very illuminating. Thank you. Are you in a position (do you
have access to the right equipment) to determine the pass-through
capability of an electricity meter?

I can't readily think of a way of setting up that test with the
installation I have. The neighbours are probably too far away to make
for a realistic test that way, and also since they rewired our overhead
supply its rather difficult to tell who is on which phase now since they
twisted the main feed along the street into a bundle.

Perhaps if one had a spare meter to experiment with... Not sure if
something like:

http://www.tlc-direct.co.uk/Products/RDCRED60.html

would be close enough to a normal domestic meter to use as a baseline.

I can verify that it does not take much filtering to block successful
connection however. A standard "filtered" extension lead is enough to
render the network either invisible or at least not able to establish a
reliable connection with. Even a backup (i.e. not online or line
interactive) UPS will block connection).

I was hoping (wishing) that you might already have access to suitable measuring equipment and be able to probe the relative HomePlug signal strengths across an installed electricity meter's input and output

Alas no - other than having ready access to some homeplug devices, and an electrical system that is reasonably well suited to certain types of empirical test.

connections. I wasn't thinking, and I don't ask, that anyone would go out of their way just to satisfy my curiosity.

Yup I realise that. However I am not aghast at the idea of spending a bit of time investigating these things out of a combination of curiosity, and also a desire to know since its something that I am sure I will increasingly get asked professionally.


--
Cheers,

John.

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