The R 976-E electric crawler excavator, along with the R 980 SME-E, replaces the ER 974 B for mine and quarry extraction. The latest electric excavators to be developed and produced by Liebherr, they are not just converted diesel machines. The excavators and their electric power systems were designed and produced entirely by Liebherr.
Robustly designed and capable of withstanding extreme conditions, they weigh 90 and 100 tonnes respectively and are available in backhoe and shovel versions. They stand out for their low noise level, versatility and zero CO2/greenhouse gas emissions during operation.
Tried and tested electric system
The electric system in the new Liebherr R 976-E 400 kW crawler excavator is supplied with 6000 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 6000 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. Thanks to its constant speed whatever the load, an excavator with an electric engine has a longer service life. Also, the high availability of transient power for complex machine movements enables very 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.
Robustness, reliability and cost-effectiveness
Liebherr excavators’ reliability has been tested in extreme conditions. In line with its commitment to ecology and sustainability, Liebherr guarantees zero pollutant gas emissions. In addition, to ensure quality, the electric power system was designed and produced entirely by Liebherr-France SAS itself.
Reduced maintenance and lower operating costs make an electric excavator more cost-effective than a diesel-engine machine. For greater comfort, the R 976-E and R 980 SME-E are extremely quiet. The robustness and cost-effectiveness of the R 976-E and R 980 SME-E make them products for environmentally friendly extraction applications.
The R 976-E and R 980 SME-E feature a spacious cab equipped with an automatic permanent air-conditioning and heating system while the exterior has a 270° camera system plus an armoured windscreen and roof window.
The operator’s platform features a large number of additional monitoring functions and a standard large 9” screen.