Keywords
Citation
(1998), "Danfoss develops new CANbus hydraulic control concept", Assembly Automation, Vol. 18 No. 3. https://doi.org/10.1108/aa.1998.03318cad.007
Publisher
:Emerald Group Publishing Limited
Copyright © 1998, MCB UP Limited
Danfoss develops new CANbus hydraulic control concept
Danfoss develops new CANbus hydraulic control concept
Keywords Communication bus, Hydraulics
Danfoss has developed a modular CANbus (controller area network, serial communication bus) control concept for its electro-hydraulic PVG 32, PVG 83 and PVG 120 proportional valves. The system is extremely compact but claims to provide a sophisticated, complex system utilising minimal electrical wiring and connectors.
As part of the package Danfoss has also developed a new CANbus-compatible joystick.
CANbus allows all the intelligent control functions in a hydraulic system to be communicated over two wires using a standard, non-proprietary and widely-used protocol. This results in a massive reduction in cabling, although the control system is fully programmable, and improves its diagnostic capability. Additionally, like any serial communications system, CANbus significantly improves flexibility so that system extensions for example adding an extra joystick involves only a simple two wire connection.
"Danfoss has always supplied proportional valves with PVE electrical activation a decentralised system in which the electronics are an integrated part of the electrical activation," explains hydraulics sales director, John Phillips. "Having the units communicate over CANbus is an exciting extension of this work."
CANbus protocols have been in use in the automobile industry since the early 1980s and there are a wide range of CANbus controls and input/output modules available, simplifying project planning and implementation.
The system is designed for the digital age and is capable of carrying significantly more information than today's analogue systems, being able to generate communication speeds of up to 1Mbit/s.
For remote diagnostics and servicing, the modems found on today's more advanced machines are simply connected to the CANbus. The new Danfoss products have been designed with this in mind and all their functions can be read and re-programmed remotely.
On the new PVG valves, ramp functions and flow limitation are incorporated as standard software, thereby making it only a question of setting or sending the desired set points.
Danfoss' new CANbus-compatible PVG valves can control up to eight PVEs, irrespective of type, as well as PVPX/PVPE relief valves. They can also be freely programmed through software. Both the PVG valves and the new joystick employ the widely used CAN-open protocol.
For further information please contact: Jonathan Smith, Danfoss Limited, UK. Tel: +44 (0) 0181 991 7000.