• Oscilloscope will be used
to examine the so called
measurement and see if it
is really possible to
identify the ‘polarized
• It will also be used with a
probe to measure the pH
if the electrolyte in a
variety of places at
various stages of all
required by Pourbaix
Left hand meter
• This has built in
memory of 40,000
• It can measure
amps, resistance and
• All stored data can be
downloaded to a
spread sheet after the
The centre meter.
• This is a multi-meter with a
RS232c (infra-red) connection
to the computer USB
• It can measure volts, amps,
resistance, heat, capacitance
• It is connected between the
breadboard zero rail and the
Cu/CuSO4 electrode and can
be used to probe the
measurements made in field
work that are replicated in
The right hand meter.
• This meter will be used to
measure actual corrosion
• It will be connected to the
anode and cathode of the
Alexander Cell and
provide the only path for
the charges from the
• There is no other source
of energy in the
• The copper board is remote
earth with zero resistance.
• The groundbed resistance is
• Pipe-to-soil measurements can
be made at test posts, one of
which is connected to the
negative rail of the
• Charges from the positive
source are conducted through
the yellow jumper to remote
• The TR can be connected to
the groundbed itself through a
red wire that is not visible in
• Data is put into the spreadsheet direct from the
• Formulae in each cell calculates the effects on the
charges as they pass through each conductive path.
• Electronic components have specified values and
variable components will be seen to have variable effects
on the data.
• The spreadsheet will display the effects of variations
• Components can be built into the breadboard to trigger
adjustments to the output controls of the energy source.
• This can be built to replicate any pipeline network.
• Photographing is difficult
because of reflections but
you can see the time and
• The oscilloscope trace is
straight line and the data
log shows the voltage
with the dry cell battery in
• The Alexander Cell is not
active as the electrolyte
sample is not bridging
between the anode and
• The left hand meter is
showing 1.3477 volts
between the blue and
• The green post is
connected to the zero
rail of the breadboard
circuit, this can be
checked by referring
to previous slides.
• In this picture you can see that
the centre meter is displaying
the same as the computer log
of the voltage of the dry cell
• 1.329volts between the green
breadboard post and the red
• The red post is not connected
directly to a breadboard rail but
used as a measuring node.
• It is connected to the
Cu/CuSO4 electrode that is
touching remote earth of Orac.
• The dry cell battery is in it’s
holder and charges resulting
from this corrosion reaction are
being drained from the
negative rail of the lower grid
of the breadboard through the
blue jumper lead.
• The charges from the reaction
are passing from the carbon
rod inside the battery to the
red rail of the breadboard.
• Red and black jumpers are
connecting through the
breadboard to the metering
• The Alexander Cell has been
activated by polishing the
• 4.5 micro-amps are passing
from the meter into the ground,
remote earth, and back into
the second base electro of the
Alexander cell to complete it’s
• The anode of the Alexander
cell is connected to the first
test post on the Orac pipeline.
• Test post 4 of the Orac
pipeline is connected to the
negative (zero) rail of the
breadboard by the white
• The dry cell battery has
• The meter displays show
the equilibrium as the
capacitance of the
• The yellow jumper
connects the groundbed
remote earth to the
positive rail of the
breadboard and there is a
capacitor built into Orac
to show what is called
• This can be seen as a straight line but events ac be seen
when the battery was disconnected and when the scope
probe was free.
• During much of my work I have seen corrosion noise and
background electrical disturbances.
• The oscilloscope allows these to be examined by
experimentation on the bench and in the field.
• I have found it impossible to see the ‘polarised potential’
kick as described by the scientists in the Hague. The
closed circuit experiment that they conducted was with a
controlled pH of the electrolyte in which there was a
narrow band that could be measured at all.
Voltages logged in Excel
• This is a selection from a period when the
battery was removed from it’s folder and
the capacitance of the system was
• It can be seen as a straight line, for this
section, but the whole log was over a
longer period and recorded voltages
during many of the events.
We can now examine real data
about corrosion cells.
• We have a few simple measurements of voltages and
some measurements of corrosion current itself.
• We have a log of voltages over a short period of time
and an oscilloscope image of electrons during a period
• We have the ability to describe a real equivalent circuit
and embed more features that we observe in field work.
• Software developers can now start to visualise how to
use higher level coding to best represent this data on
displays and for the computer to make real science-
based calculations to analyse real cathodic protection
Podemos agora examinar os dados
reais sobre as células de corrosão.
• Temos algumas medidas simples de tensões e algumas medições
da própria corrente de corrosão.
• Temos um registo das tensões ao longo de um período curto de
uma imagem osciloscópio de electrões tempo e durante um período
• Temos a capacidade para descrever um circuito equivalente real e
incorporar mais recursos que observamos no trabalho de campo.
• Os desenvolvedores de software podem agora começar a visualizar
como usar maior codificação nível para melhor representar esses
dados em monitores e para o computador para fazer cálculos
baseados na ciência reais para analisar sistemas reais de proteção
What is all this about?
• Millions of voltage measurements are recorded and
represented in graphs.
• People pretend that they can interpret these readings to
determine if corrosion has been controlled.
• They even describe some values a s ‘protected’ and
investors believe that they have controlled corrosion.
• Pipelines leak due to corrosion that is claimed to have
been controlled and everybody blames everybody else.
• I am seeking to rationalize this situation using computer
power and the first job is to examine the credibility of the
O que é tudo isso?
• Milhões de medições de tensão são registrados e
representadas em gráficos.
As pessoas fingem que eles podem interpretar estas
leituras para determinar se a corrosão tem sido
Eles ainda descrever alguns valores de S 'protegidas' e
os investidores acreditam que eles têm controlado a
Pipelines vazar devido à corrosão que é reivindicado ter
sido controlada e todos culpam todo mundo.
Estou buscando racionalizar esta situação usando
alimentação do computador e o primeiro trabalho é
examinar a credibilidade da entrada de dados.
Observe the voltages and micro-
• 1.329 volts is seen on the data logger display from the
RS232c connected to the centre meter. This meter is
connected between the negative rail (zero) and the
copper in the copper-sulphate solution.
• The Oscilloscope display can show the wave forms of
• 1.3477 is the measurement of the dry cell battery
through the conductive paths seen in the sketch.
• The porous plug of the Cu/CuSO4 electrode is in contact
with the remote earth plate of Orac.
• The positive of the battery (corrosion cell) is connected
to the active rail of the breadboard and through to Orac
• The data logger is recording 1.366 volts between
the Cu/CuSO4 electrode and the negative rail on
the breadboard that is the zero of this circuit.
• The battery is discharging current into the
system and 7.1 micro-amps are passing through
the meter on the right. We do not know why.
• The left hand meter is displaying 1.3477 volts
between the positive rail of the breadboard and
the zero rail. The paths of these charges can be
seen by following the black lines on the sketch.
Alexander Cell in circuit
• The electrolyte sample is
bridging the anode and
the cathode allowing
current to flow through
• The anode of this
corrosion cell is
connected to Orac test
• Orac pipeline 1 is
variable resistors to
pipelines 2 and 3.
• The resistors in the pipelines underneath Orac
can be used to simulate different lengths of steel
pipelines buried between isolation joints.
• I have added random fixed capacitors that
produce a ‘depolarisation time’ on the
oscilloscope and the data logger.
• We find that the depolarisation of the Alexander
Cell itself can be recorded when the cathodic
protection is switched off.
• We find this feature in case studies of field work
and need to model this on our computer.
Impressed cathodic protection
• The actual CP circuit can only be measured at
nodes such as isolation joints and junction
We can apply this data to our
• We simply feed the data from the meters into the
• This is all that is done by the instruments that
are sold at present for CP work.
• They only display voltages in graphic form and
do not analyse the cathodic protection circuit.
• We can apply Ohms and Kirchhoffs laws to our
spreadsheet, as I have already done in the
Dynamic Project itself.
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Dec. 8, 2020
stage 2 of project to computerize cathodic protection