Page 14 - Energize January 2022

NEWS

Energy efficient electric motors for mines

BMG has developed high efficiency electric motors which set the benchmark for arduous duty

MG’s flagship Synergy range of asynchronous cast iron motors complies with the modification time and reduces stocks.
efficiency requirements as stipulated in SANS 60034-30:2009 and has SABS certification, An SPM bearing monitoring device
Bwhich translates into production efficiency advantages for the local market. is an option that can be installed for
Standard Synergy three-phase asynchronous cast iron motors encompass the latest continuous monitoring of the bearing
technology in electric motor design and are used in many industries, including mining condition.
and metallurgy, pumps and water treatment, petroleum, chemical, cement and sugar and Synergy has also developed aluminium
paper milling. housing motors, with cast iron end shields,
BMG supplies a full range of Synergy IE3 motors ex-stock and can also supply IE4 and IE5 for frame sizes up to 180. Advantages of
units from the factory, to meet exact requirements on each mine. this design include a robust structure and
“Almost two thirds of the power consumed by the mining sector is associated with reduced noise.
electric motors, particularly those used for pumps, fans and conveyors. The majority of BMG’s electromechanical division is
motors on the mines are not optimised for maximum efficiency,” says Graeme Neilson, uniquely positioned to meet the exact
BMG’s business unit manager for electric motors. “Apart from energy saving – a critical gear drive and motor requirements of
issue facing Southern Africa – Synergy motors have important advantages over other contractors, designers and the end-
electric motors. These benefits include longer service life, suitability for voltage variation user in diverse industries. A team of
applications, reduced temperature rise and minimal maintenance requirements. Synergy technicians, with extensive experience,
motors also offer reduced noise and vibration levels, higher reliability, greater flexibility and offers a technical advisory and support
lower cost of operation.” service and a substantial stockholding is
Synergy IE3 motors incorporate high level specifications and features, including an IP66 held at BMG World, for quick and efficient
rating for protection against the ingress of dust and water and an oversized terminal box delivery throughout the entire Southern
with a removable gland plate, for easy replacement of the cables. Class H insulation, with African region.
a Class B (80°C) temperature rise, means the insulation can safely withstand heat that is
higher than the motor’s operating temperature at full load. Motors from frame size 80 to Contact Graeme Neilson, BMG,
132 have sealed bearings and all motors 160 frame and above have re-greaseable bearings. Phone 011 620-1690,
The standard lubrication nipples are manufactured from brass or stainless steel and are graemen@bmgworld.net,
suitable for all environments. www.bmgworld.net
These motors have a rated voltage of 400 V and 525 V at 50 Hz. The efficiency and
power factor values of this range ensure cost efficiency, with a return on the
investment of between three and five years.
An important performance feature is that Synergy motors are
most efficient when running between 75% and 100% of full load.
An electronic soft starter – which controls parameters like
current and voltage – ensures the starting sequence is efficiently
controlled. Standard motors operate at fixed speed, regardless of the
actual output required, while Synergy motors can operate efficiently,
without cogging at low speed, in conjunction with a variable speed
drive (VSD), reducing energy consumption by over 50%. VSDs
are designed to manipulate power from a constant three-
phase 50 Hz supply, converting it to variable frequency. This
enables the speed of the motor to be controlled to achieve
maximum efficiency at the required load.
The Synergy IE3 motor has undergone surface
treatment to ensure extended service life in harsh mining
conditions. For maximum flexibility during installation,
both integrated and removable feet are available. Solid
motor feet provide a more resistant structure against
vibration, while removable feet can be placed on different
positions of the motor frame. The latest design allows the
terminal box to be mounted top, right or left and the cable entry can
be rotated 360°, without disassembling the complete motor. This minimises

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