Rotary encoders give any number of reference points according to the respective resolving power - coded position values. In comparison, incremental systems give impulses and usually only one reference point corresponding to a change of position. The impulses need to be counted in a control system and the reference point often needs to be started up in a complicated and time-consuming way after stoppage or malfunction.

From parallel data transfer to encoders with field bus technology.

Since the beginning of the nineties, bus technology and especially open field bus technologies like Profibus, Interbus, DeviceNet and CANbus are increasingly used. In contrast to traditional and conventional techniques, they are considered to be economically interesting. Field busses are not only less expensive than the conventional systems, but they represent a new technology, which allows a new dimension in the way of thinking about new systems. Field bus technologies are usually the nerves of modern automation facilities. They enable selective and efficient communication between the components of automation facilities -the bus nodes. Different types of bus nodes are distinguished according to their type of function. The encoder as a position value transmitter belongs to the group of sensor nodes. Control and regulation devices applied in modern automation facilities don’t use any integer data from sensor nodes or encoders; they use pre-processed and filtered values in a standardized readout. The pre-processing comes from the encoders respectively over the bus. Additionally, alarms can be triggered, diagnosis data transferred or any exceeding of pre-given setting values indicated as a result from the sensor nodes.

Encoders with field bus interface for the user’s versatile applications.

INNOTICS has designed a complete family of encoders with field bus interfaces. INNOTICS offers the CAN-bus interface for CANopen and DeviceNet-Applications, furthermore Profibus-DP and Interbus. The encoders can be configured via the field bus. One encoder type is applicable for different tasks - which also results in a simplified stock keeping for the user.

All INNOTICS field bus encoders passed the various conformity tests. They are certified and fulfilled or exceed all requirements. The INNOTICS standard encoder has a maximum basic resolution of 8192 steps per revolution (13 bit).

In the multi-turn model up to 4096 revolutions are detectable (12 bit). Powerful micro controllers upgrade field bus technology The utilization of processors in the encoder opens great potentials for further development. With the processor’s intelligence in the encoders, it is now possible to adopt functions that go beyond a simple positioning. Integrated systems of the intelligent multi-sensors are developed to control whole axes - up to an active axis controller for local motion control solutions.