Cost savings
May 1st 2008 A plant wide energy efficiency
installation is saving £120 000 a
year in the woodworking shops at
door and mouldings company
BLP in Doncaster. The system is
based on variable speed drives,
PLCs and HMIs from Mitsubishi
Electric and is being expanded.
Moulding machines have eight
cutting spindles with individual
forced draught extraction heads
feeding a series of manifolds into
a central air handling system. In
trials, Mitsubishi Electric blanked
off nozzles and ramped down
motor speeds. Results showed
speeds could be reduced from
50Hz full power to 37Hz without
loss of performance.
A subsequent pilot scheme on
two moulding machines used
pneumatic valves to close off
individual suction heads and a
Mitsubishi drive to reduce motor
speeds or even isolate the entire
machine's extraction. The
company saved £10k of energy
expenditure in just 12 months.
The need for greater control
prompted Mitsubishi to suggest a
simple yet powerful control
architecture based on four
supervisory PLCs and three HMIs
for local control. More articles from Mitsubishi Electric Europe: | 
