The new Liebherr R 976-E and R 980 SME-E electric crawler excavators, weighing 90 and 100 tonnes respectively, are available in both backhoe and shovel versions. Developed and produced by Liebherr-France SAS in Colmar, France, these latest models stand out for their low noise level, optimum versatility and local zero emissions during operation. They replace the ER 974 B for mining and quarry applications.
The electric system in the new R 976-E 400-kW excavator is supplied with 6,000 V power via a cable connection, with the cable inlet in the centre of the undercarriage, or on the sides if requested. A motor cable drum is also available as an option. The machine is powered by a high-voltage 6,000 V/50 Hz current collector. A switch cabinet transformer (high voltage/low voltage) and a low-voltage cabinet for power distribution and control of 690 V, 230 V and 24 V networks are located on the upper carriage.
The technology used in the R 976-E and R 980 SME-E offers a host of advantages, explained Liebherr. Thanks to its constant speed whatever the load, an excavator with an electric engine has a long service life. Also, the high availability of transient power for complex machine movements enables high productivity.
The R 976-E’s low-voltage electric squirrel-cage engine drives the hydraulic system. The engine features heat shielding on bearings and motor windings. Integrated into a frame with a reinforced flange, it enables safe, soft starting.
The two robust electrical cabinets are assembled by welding into a structure specifically designed to withstand extreme working conditions. The lockable watertight (IP 65) doors are fitted with safety switches and an emergency stop. The high-voltage cabinet is a dedicated contact for power connection and voltage transformer, while the low-voltage cabinet is used for power connection monitoring.
According to Liebherr, the machines’ reliability has been tested in extreme conditions. The company also guarantees zero pollutant gas emissions, in line with its commitment to ecology and sustainability.
In addition, the new R 976-E and R 980 SME-E excavators offer comfort and safety for the operators. The machines’ spacious cab is equipped with an automatic permanent air-conditioning and heating system, while their exterior has a 270° camera system plus an armoured windscreen and roof window. The operator’s platform also features a large number of additional monitoring functions and a standard large 9-in screen.