tramming a movable carrier of the rock drilling rig by at least one hydraulic tramming actuator;

operating at least one rock drilling unit provided with hydraulic drilling actuators selected from: at least one hydraulic percussion device, at least one hydraulic rotating device and at least one hydraulic feed device;

generating hydraulic power to at least one hydraulic system by at least one hydraulic pump driven by at least one electric motor EM connected to at least one electric system of the rock drilling rig;

controlling the tramming and drilling measures of the rock drilling rig by an operating system;

using one common hydraulic pump of the at least one hydraulic pump and one common electric motor of the at least one electric motor for generating hydraulic power selectively to a first closed loop hydraulic circuit being in fluid connection with the at least one hydraulic tramming actuator and provided with by-pass flow channels for allowing cooling and filtering of the hydraulic fluid circulating in said closed loop hydraulic circuit, and to a first open loop hydraulic circuit being in fluid connection to the at least one hydraulic drilling actuator; and

executing the selection between the first closed loop hydraulic circuit and first open loop hydraulic circuit under control of the operating system.