Subject: (Philips) Current Flow on Water Pipes Between Houses (fwd)
Date: Wed, 26 Aug 1998 063913 -0500 (CDT)
From: "Roy L. Beavers" <rbeavers@llion.org>
To: emfguru@hotmail.com
--------------------------------------------------
---------- Forwarded message ----------
Date: Wed, 26 Aug 1998 11:05:44
From: Alasdair Philips
To: "Roy L. Beavers"
Subject: Current Flow on Water Pipes Between Houses (fwd)
Roy - some comments:
>---------- Forwarded message ----------
>From: Stewart Fist
>There's been a lot of discussion recently about water pipes and
>'dielectric' unions. I must be ignorant here, or there's a
>terminological problem between Australian English and US English.
>Do people mean 'non-conductive',or are they implying inductive coupling?
>-----------------------------------------------------------------
STEWART IS CORRECT. "NON-CONDUCTIVE" IS THE TERM WHICH SHOULD BE USED.
'DIELECTRIC' MEANS "A MEASUREMENT OF THE ABILITY TO TRANSMIT ELECTRIC
EFFECTS WITHOUT CONDUCTING"! THE EFFECT IS USED IN CAPACITORS WHICH DOUBLE
THE AMOUNT THEY CAN PASS AS THE FREQUENCY DOUBLES - THEREFORE A DIELECTRIC
COUPLING ON A PIPE WOULD REJECT THE 50/60HZ BUT PASS SOME HIGH FREQUENCY
TRANSIENT SIGNALS.
------------------------------------------------------------------
>From: Envoptions@aol.com - Spark Burmaster
>Subject: SX1: Current Flow on Water Pipes Between Houses
>This is in reference to thepostings on the putting of a dielectric
>union in the water service supply pipe of a house.
>I wish to comment on these three issues.
>1) Electrical Safety
>2) Biological Issues
>3) Proper use of terms to avoid confusion.
I AGREED WITH MOST OF WHAT SPARK WROTE BUT FOUND SOME OF HIS WORDS
HAD TO BE READ MORE THAN ONCE. I WISH TO COMMENT ON SOME POINTS:
1/ SAFETY
IN MOST COUNTRIES NOW IT IS A LEGAL REQUIREMENT THAT ALL METAL PIPEWORK
WITHIN A HOUSE IS ELECTRICALLY BONDED TO THE ELECTRICAL SAFETY EARTH TO
PREVENT THE POSSIBILITY OF ELECTRIC SHOCK. IN MOST EUROPEAN COUNTRIES IT
IS NOW NO LONGER LEGAL TO RELY ON AN INCOMING WATER PIPE TO PROVIDE AN
ELECTRICAL EARTH - THIS IS BECAUSE MANY WATERS MAINS ARE BEING REPLACED
WITH PLASTIC PIPES.
THE ELECTRICAL 'EARTH' CONNECTION IS EITHER SUPPLIED BY THE ELECTRICAL
UTILITY OR IT CAN BE A SEPARATE "EARTH STAKE" IN THE GROUND WHICH HAS BEEN
TESTED FOR A LOW ELECTRICAL IMPEDANCE FOR THE ELECTRICITY (IE EFFECTIVELY
TO THE NEAREST SUBSTATION TRANSFORMER) BY DUMPING A SUBSTANTIAL CURRENT
(SEVERAL AMPS)INTO IT AND MEASURING ITS EFFECTIVE IMPEDANCE. (The tests are
usually defined in the Electrical Regulations /Codes and Annexes).
IT IS BEST THAT ALL INCOMING METAL PIPES HAVE INSULATING/NON-CONDUCTING
SECTIONS IN THEM AND ARE ONLY CONNECTED TO THE "ELECTRICAL SAFETY EARTH"
WITHIN THE HOUSE ITSELF. (TO COMPLY WITH THE REGUATIONS/CODES)
MANY/MOST UTILITIES AROUND THE WORLD SUPPLY LOW VOLTAGE AS A THREE-PHASE
PLUS NEUTRAL STAR SUPPLY WHICH HAS THE 110/230 VOLT SINGLE PHASE SUPPLIES
WHICH FEED MOST HOUSES TAKEN ACROSS ONE (VARYING from house to house)PHASE
TO NEUTRAL. IN ORDER TO HELP PREVENT LARGE "OVER-VOLTAGES" OCCURRING UNDER
FAULT CONDITIONS THEY CONNECT THE NEUTRALS ON NEIGHBOURING SUBSTATIONS
TOGETHER (THE VERY PRACTICE THAT SPARK AND KARL STATE IS A 'NO-NO' WITHIN A
BUILDING) AND THIS CAN LEAD TO LARGE (I HAVE MEASURED 384 AMPS!) NET ERROR
CURRENTS FLOWING AROUND URBAN DISTRICTS ELEVATING MAGNETIC FIELDS OVER
LARGE AREAS.
AS THE SUPPLY NETURALS ARE ALSO CONNECTED TO "GROUND" AT THE SUBSTATIONS
AND IN THE CASE OF PME (PROTECTIVE MULTIPLE EARTHING) SYSTEMS AT REGULAR
INTERVALS AROUND THE DISTRICT, THESE ERROR CURRENTS END UP ON METAL WATER
AND GAS PIPES, ENTER A HOUSE, AND RETURN OUT FROM THE HOUSE ON THE
ELECTRICITY COMPANY SUPPLIED EARTH WHICH HAS BEEN CONNECTED TO THE PIPES
INSIDE THE HOUSE AS REQUIRED BY THE REGULATIONS.
I HAVE MEASURED 43 AMPS FLOWING INTO ONE HOUSE IN THIS WAY. WHEN I CUT THE
PIPE THE VOLTAGE WAS ONLY A COUPLE OF VOLTS BETWEEN THE CUT ENDS BECAUSE
THE IMPEDANCE WAS SO LOW - SO THERE WAS NO DANGER OF ELECTRIC SHOCK, JUST
ELEVATED MAGNETIC FIELDS IN THE ORDER OF 150mG (15uT) IN MANY AREAS OF THE
HOUSE AS THE WATER PIPE CAME IN ONE SIDE AND THE ELECTRICITY EARTH THE
OPPOSITE SIDE OF THE BUILDING. AFTER INSTALLING THE NON-CONDUCTIVE PIPE
SECTION THE HOUSE MAGNETIC FIELDS FELL TO 0.5mG (0.05uT). A CLAMP-METER
CAN BE USED AROUND PIPES TO EASILY CHECK WHAT CURRENT IS FLOWING IN THEM.
2/ - WE SHOULD CONSIDER ALL "EMFS" ARE POTENTIALLY SLIGHTLY BIO-ACTIVE.
3/ TERMINOLOGY
WHEN I WAS AT SCHOOL EMF STOOD FOR ELECTRO-MOTIVE-FORCE I.E. A VOLTAGE.
THAT NOW SEEMS TO HAVE BEEN RELUGATED TO "emf".
LANGUAGE CHANGES AND EVOLVES AND NOW "EMF" IS GENERALLY TAKEN TO MEAN ANY
TIME-VARYING ELECTRIC OR MAGNETIC FIELD, WHETHER OR NOT IT IS RADIATING.
IT THEN HAS TO BE REFINED IF NECESSARY BY ADDING:
SLF (UP TO 30 Hz)/ ELF (30 - 300Hz) / VF (voice 300-3kHz)/
VLF (3 - 30 kHz) / LF (30 - 300 kHz) / MF (300k - 3MHz) /
HF (3 - 30 MHz) / VHF (30 - 300 MHz) / UHF (300 MHz - 3 GHz)
SHF (3 - 30 GHz) / EHF (30 - 300 GHz) (the SI designators I am told)
....AND THE SOURCE! The source is important because whereas 50 / 60 Hz
mains fields are "near field" concerns with electric and magnetic fields
being quite separate and not mathematically related, Schumann waves (c 8 to
32 Hz) are actual radiated fields resonating in the Earth/Ionosphere cavity
and do obey Maxwell's radiation equations! Maybe that difference is
important. However even man-made 50 and 60 Hz fields DO radiate from long
transmission lines and have been measured in space at great distances from
the Earth.
So, I think the generic use of "EMF" to mean any time-varying electric or
magnetic fields is now generally accepted as modern parlance. It should not
be used in isolation without describing the source and the frequencies
involved. For example a 200 kHz long-wave radio transmitter of which we
have some very powerful (eg 500kW) ones in the UK has a wavelength of 1500
metres (ie about 1 mile) so anyone within about 200 metres would be almost
exclusively in the near field anyone over about 500 metres in the far field
and those in between these distance - who knows! There ain't any simple
answers and I don't think being pedantic about the accepted meaning of
'EMF' helps our precautionary cause.
I do exclusively use the terms "electric" and "magnetic" fields when
talking to people and in my Reports but EMF is a good generic term that
many of the great unindoctrinated public are just beginning to cotton on to
as maybe something to watch out for and be concerned about. Even the World
Health Organisation EMF Project includes power frequency fields!
Good wishes to all
Alasdair
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Alasdair Philips (aphilips@gn.apc.org)
Director, UK Powerwatch,
EMC Engineer and EMF-bioeffects researcher
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Archive provided courtesy of WaveGuide, http://www.wave-guide.org
Reprinted with permission of Roy Beavers, http://www.feb.se/EMF-L/EMF-L.html