Double the life span of your variable
speed drives for less per day than the
cost of a cup of coffee
he idea that living things
shut down instead of
wearing down has received
substantial support in
recent years. Researchers
working on the now famous worm
C.elegans (the little nematode worm
behind research that led scientists to
receive the Nobel Prize, not just once but
twice, in a decade) were able to produce
worms that live more than twice as long
and age more slowly, simply by altering a
single gene. Scientists have since come up
with single gene alterations that increase
the life spans of fruit flies, mice and yeast –
and Quantum Controls have come up with
a solution that will double the life span of
your variable speed drives.
T
A little bit of history
The majority of evidence goes against the
idea that our life spans are programmed
into us. For most of our 100,000 year
existence - excluding the last couple of
hundred years - the average human life
span has been 30 years or less. Research
shows that subjects of the Roman Empire
had a life expectancy of 28 years. The
natural course was to die before old
age. Indeed, for most of history, death
was a risk at every stage of life and had
no obvious connection with ageing at
all. As Montaigne wrote, in the late 16th
century: “to die of old age is a death rare,
extraordinary and singular, and therefore
so much less natural than the others: it is
the last and most extreme sort of dying”.
So today, with our average life span in
much of the world climbing past 80 years,
we are already oddities living well beyond
our appointed time. When we study
ageing, what we are trying to understand
is not so much a natural process as an
unnatural one.
Leonid Gavrilov, a researcher at the
University of Chicago, USA, argues that
human beings fail the way all complex
systems fail: randomly and gradually.
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PECM Issue 28
Getting back to equipment
As us engineers have long recognised,
simple devices typically do not age. They
function reliably until a critical component
fails, and the whole thing dies in an
instant. A variable speed drive for instance,
works smoothly until the capacitors start
discharging dielectric or IGBT devices fail,
and then it does not work at all.
But complex systems - such as your
manufacturing process - have to survive
and function despite having many key
critical components such as motors
and drives. That’s why engineers design
machines and production processes
with multiple layers of redundancy: with
backup systems, and backup systems for
the backup systems. These may not be as
efficient as the first line components, but
they can allow the machine and process
to keep running even when damage
accumulates.
Unless process equipment is correctly
maintained, the defects in your process
equipment increase until the time comes
when just one more defect is enough to
stop your whole process. With the average
cost of one hour of lost production due to
drive failure in UK manufacturing being
£12,000, this condition known as frailty
must be avoided, and it sits with engineers
like ourselves to prevent this occurring.
Coming full circle
It happens to motors, variable speed
drives, softstarts and it happens to us -
eventually too many joints are damaged
or one too many arteries calcify. There are
no backups. We wear down until we can’t
wear down anymore.
But we can avoid and slow th