When Eco Log launched the 688G harvester, it marked a clear technological shift – not least in hydraulics, drivetrain, and control systems. The machine is essentially a new platform where the hydraulic system has been redesigned from the ground up, with strong system integration in collaboration with Bosch Rexroth.
Fully integrated hydraulic system with a focus on software
At the core of the 688G is a new, fully integrated hydraulic system where pumps, valves, motors, and control have been developed as a unified system. This type of system design is becoming increasingly common in mobile machinery, where functionality is progressively shifting from hardware to software.
A key component is the latest generation of eOC pumps (Electronic Open Circuit). These enable electrohydraulic control of flow, pressure, and power via software, providing high dynamics and the ability to optimize energy usage in real time. The combination of pump control and software can also reduce both fuel consumption and system complexity.
RM Global – new valve platform in the field
One of the most notable innovations is the implementation of Bosch Rexroth’s RM Global valve platform. The Eco Log 688G is the first machine globally where this modular load-sensing valve is used in real-world operation.
The valve platform is based on modular sections (RM10 and RM15) with flow-optimized channels and working pressures up to 420 bar. The result is improved precision in crane movements, reduced leakage, and more energy-efficient operation. At the same time, the compact design enables reduced system weight and easier integration.
Automatic calibration and reduced service needs
A clear trend in the 688G is an increased level of self-adaptation. The hydraulic system can automatically calibrate pump pressure and system parameters without manual adjustment. This reduces the need for field adjustments and simplifies both commissioning and service.
This represents a step toward more autonomous hydraulic systems where the machine optimizes its own performance based on load and working conditions.
Updated transmission and drivetrain
The drivetrain has also undergone a major upgrade. The hydrostatic-mechanical transmission features a new hydraulic pump and motor, delivering a tractive force of approximately 230 kN and improved drivability in varying terrain.
The integration between transmission and working hydraulics is tighter than before, enabling a better balance between propulsion and crane operation – particularly important in steep and sensitive terrain.
Adaptive driving modes and system response
The machine offers several driving modes – Comfort, Balanced, Dynamic, and a Boost mode – where hydraulic response and power output are adapted to the situation. This illustrates how the control system leverages the electrohydraulic architecture to give the operator more direct control over machine behavior.
Increased capacity in working hydraulics
The crane hydraulics have been upgraded with higher flow and capacity, resulting in increased lifting force and faster movements. Together with improved valve control, this provides a more responsive machine in practical operation.
Summary: Shift toward software-defined hydraulics
The Eco Log 688G clearly shows the direction for future forestry machines:
- Electronically controlled pumps
- Modular valve platforms
- Integrated system solutions
- Self-calibrating functions
The result is a machine with higher precision, improved energy efficiency, and reduced need for manual adjustments – while increasing complexity is handled more by software than by individual components.
