MOTORS
WWW.MADEIN.IE « JUNE 2020 « 31
estimated that a 10°C reduction in
operating temperature typically doubles
the motor’s lifetime.
The innovative software allowed for a
special start up function when starting
the jaw crusher from full. In the event
that the crusher is stopped full, the VSD is
able to be remotely activated in an
unblock mode, with a very fast ramp time
in forward or reverse depending on the
position of the crusher. It will
continue to automatically
control the direction,
current, ramp times, DC
bus voltage, torque,
position, and speed
until the product in the
chamber has been
cleared and the crusher
has run empty for a set
period of time. This
innovative system removes
the dangerous and laborious
job operators have had to do for
years, by manually unblocking jaw
crushers using rock breakers or winches
to remove product.
Another very important part of the
system was the alternator, which is vital to
achieving an efficient and reliable system.
According to the International Energy
Agency (IEA), 16 per cent of motor
failures are due to external conditions,
such as contamination, so ensuring
application suitability was essential. The
alternator selected was from the WEG
G-line range with some special features
such as a dust filtering system, to allow it
to operate in a dusty quarry atmosphere,
without the risk of foreign particles
entering the system. The alternator also
included a digital input AVR to allow
remote voltage adjustment, standard
I-PMG auxiliary winding system feature to
allow a dynamic response to load change
and short envelope compared to
traditional external PMG alternators.
“The complete drive system was
expertly selected to work in harmony to
address many issues manufactures in the
industry come across,” explained
David Strain, technical director
at Technidrive. “The added
unblocking feature
transforms the starting
of the application, an
often energy intensive
process and provides a
unique benefit for
system safety. With the
system supplied, we are
able to provide a three-year
warranty for the motor and
inverter and ensure the three main
parts to the drive system all work together
for optimum performance and reliability.
Since our first jaw crusher project, we
have had much interest from other
businesses in the quarrying industry. We
treat each project on an individual basis,
to offer bespoke turnkey systems.”
“WEG offers specialist products that are
developed specifically for the rock
crushing industry,” explained Russell
Maccabe UK Sales Manager at WEG. “It’s
vital that manufacturers and suppliers
both have extensive product, application
and systems integration knowledge and
that’s why this project with Technidrive
proved to be so successful.” MADE
selected with an output sinusoidal filter to
create a nice sine wave, reduce output
current and importantly reduce electrical
noise.
Electrical disturbances however aren’t
the only consideration, crusher blockages
can be a real problem for operators,
resulting in periods of prolonged
downtime. One of the main advantages of
this project was the level of control that
was achieved through an innovative piece
of software, which Technidrive developed.
On a normal start from empty, the VSD
ramps the crusher up on a slow ramp time,
restricting the absorbed current due to the
high inertia of the application. This not
only keeps the power supply requirements
low, for a more efficient system, but also
reduces the stress on the mechanical
system. Over time this can lead to
significant maintenance cost savings and
extend the life of the machine. It’s
Rock enters
the jaw crusher
from the top of the
machine and gets
compressed
between two
surfaces
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