| faqs
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| why source engineering?
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 We are a new company with a wealth of experience and knowledge
in battery and UPS engineering. We provide a full service, from
battery builds to safe disposal, saving you time to run your
business. We started the company to meet the demand from our
existing business as UPS engineers. Our engineers have worked as
service partners to some of the leading, blue chip companies in
Ireland. They have also worked in organisations where they have
been responsible for back up power and understand the enormity
of not having reliable back up systems and of the difficulties
in finding the right suppliers to replace, test, install and
maintain industrial batteries.
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| We are an honest and straightforward company with customer
focused standards and procedures. Our solutions will provide
your organisation with an inexpensive, safe and intelligent
approach to power provision. We make it as easy as possible to
do business with us and we work hard at building sustainable
partnerships with our clients.
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| what type of batteries do we test?
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| There are two main types of SLA (Stationery Lead Acid)
industrial batteries that our clients use:
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Flooded (wet) cells
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Flooded cells are traditionally tested by
hydrometer to indicate the state of charge
of a battery by sampling the electrolyte.
Now conductive testing is more recognised
but complimented by digital SG meter (which
electronically compensates temperature) to
determine true state of health of battery.
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VRLA (Valve Regulated Lead Acid)
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VRLA's are 'maintenance free' therefore only
Ohmic testing is possible.
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| why conductance testing?
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 In the simplest technical terms, Ohmic technology is based
on Ohm's law, which expresses the relationship between volts,
amperes and ohms in an electrical circuit. Ohmic technology
attempts to use voltage and current to determine the resistive
characteristic of a battery. Higher resistance equates to a
reduced ability to produce current. This characteristic is
translated into a measurement of resistance or impedance (Ohms)
in some Ohmic technologies; more recent technology uses a
converse measurement called conductance.
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| what is conductance technology?
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| Conductance is a measurement of a batteries ability to produce
current or of its electrical safety. It is calculated in a
value called Siemens.
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| Evidence of a battery's state of health can be identified
when comparing conductance measurement from similar cells in a
battery system. The higher the conductance value (or lower
internal resistance), the better the expected performance
potential from the cell.
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 To measure a battery's conductance, a signal is sent through the
battery and a portion of the AC current response is calculated.
Conductance is the equivalent measurement of the plate surface
available in the battery for chemical energy exchange, which
determines how much power the battery can supply. As a battery
ages, the plate surface can sulphate, shed active material and
change chemically, adversely affecting the battery's ability to
perform. This normal aging process will cause conductance to
decrease gradually as the cell service life is consumed. For
power provision, this means that conductance can be used to detect
cell defects, shorts and open circuits which reduce the ability of
the battery to deliver current.
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| Conductance test measurements become the equivalent of a
battery's true state of health diagnosis.
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| why use conductance to identify failures?
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| Failure of VRLA batteries is accompanied by a decrease in the
cell's conductance. Post seal, jar-cover leakage, positive
grid corrosion and valve malfunction result in cell dry-out,
thereby decreasing capacity and conductance. The loss of grid
contact, loss of separator compression, electrolyte
stratification, grid corrosion and loss of contact in the top
lead work all result in loss of capacity as well as conductance.
Thus when applied to SLA batteries, battery conductance
monitoring will provide us with a clear indication of the
batteries state of health.
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| what is battery health?
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 Another benefit of Ohmic monitoring and testing is the ability
to predict end of life for battery cells and strings. Rather
than just identifying 'bad' cells, Ohmic testing can measure
battery health over time. By regularly measuring conductance
from time of installation, changes in measured conductance and
the corresponding expected loss of capacity can be observed and
trends identified.
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| what is best practice?
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| Current IEEE battery maintenance standards advise Ohmic testing
of all batteries at least once a quarter. Additional independent
research carried out by the Electric Power Research Institute
(EPRI) states that 'utilities can implement more
cost-effective battery test methods and realise a more stationery
battery installation using Ohmic measurements'.
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| The idea is based on understanding the capacity, or conductance
for a new healthy battery. By using the measured conductance
value of an 'optimised' cell, a technician can develop a
replacement strategy as conductance degrades over time.
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