VLT® drives give 30-year-old new lease on life
The enormous 800 tonne machine is now modernized, to regenerate energy, start at high torque and adjust its speed according to current ground conditions. New smoothed acceleration will extend its gear lifetime into the coming decades.
VLT® AutomationDrive FC 302 frequency converters with PROFIBUS communication are installed for motor control in
- the three pairs of horizontal movement caterpillars, which move the excavator from site to site in the open-cut mine. Power is supplied via a 3x500 V IT mains system. Each 55 kW, 1000 RPM motor starts with torque reaching up to 230% of the continuous rated motor torque.
- the jib, which digs up coal via a series of buckets on an extended arm.
- the revolution control, which enables the head of the excavator to rotate via a gigantic main rotary gear.
Regenerative modules ensure an overall energy efficient solution, including regeneration when the excavator is travelling downhill. Relocating 800 tonnes is absolutely no mean feat, so there are certainly compelling savings to enjoy with its renewed longevity.