CiA 408 profile specifies the CANopen communication and application functions for hydrostatic transmissions (e.g. drive, axis),  hydraulic proportional valves, and hydrostatic pumps and can also be applied to pneumatic devices. The current version is based on the network-technology-independent proposal “VDMA profile fluid power technology. Proportional valves and hydrostatic transmissions, version 1.6.3” from VDMA (German association of machine builders). Thus, VDMA-compliant hydraulic devices using different networking technologies can be easily combined in one system. The specified application data is then exchanged via corresponding gateways. The device manufacturer may supply diverse markets with valves, pumps, pneumatics, etc. implementing the same electronic interface according to CiA 408 and simply varying the appropriate application software. Usage of standardized CANopen interfaces allows monitoring, inspection, and diagnostics of the networked devices using off-the-shelf tools.

The profile specifies the required configuration parameters, application parameters (process data), and diagnostic information. Parameters for drive, valve and pump reside in the same CANopen logical device. This allows one electronic circuit for control of drive, valve and pump module or independent control of up to eight such modules or 8 devices of the same type e.g. drives.

Application parameters for up to 15 control modes are defined. The modes can include the (mixed) control of spool position, pressure, speed, power, velocity, position, and flow. The application parameter assignment within each control mode is done according to a defined schema. After the control-mode-specific parameter definitions the set-point conditioning (e.g. limit, scaling, ramp) and actuator conditioning (e.g. zero correction, dead-band compensation) is defined. Control monitoring, auxiliary functions and target window monitoring finalize the parameters for each control mode. The description of application parameters consists of parameter values (16-bit, 32-bit integer or floating-point value), as well as the corresponding SI unit and prefix with coding as specified in CiA 890 (formerly CiA 303-2). The application parameters are defined in the VDMA profile by the attribute name, data type, substitute value, default value, value range, access rights, and object class. The nine defined TPDO and ten defined RPDO (process data object) mapping variants depend on the device control mode and are different for drives and valves (except for mapping 1).

The introduced device finite state automaton (FSA) specifies the application behavior as well as the corresponding state transitions of the hydraulic devices. A specific device FSA state transition may cause a state transition in the CANopen communication FSA (see CiA 301) and vice versa. The devices compliant with this profile are required to support the emergency message as specified in CiA 301. CiA 408 compliant CANopen devices supporting the application manager functionality also provide the CANopen network management (NMT) manager functionality.