Kuhnke have been producing PLC's with bus interfaces since 1993 when the first PROFIBUS cards were produced for the Kuhnke 657 rack system. The Kuhnke 657 PLC then represented old centralised control with many I/O's located in a single unit, hardwired via cable bundles to sensors and actuators. Soon after this, decentralisation took hold in machine and factory automation and new generations of Kuhnke product were developed to meet this demand.
Kuhnke's main PLC range, the 680, 690 and 691 series are now available with integrated PROFIBUS DP. Most of these products have also been available in CANopen format since 2000. Kuhnke are releasing more and more products with both PROFIBUS and CANopen bus interfaces.
Note that PROFIBUS FMS (master to master communication protocol) is now being dropped in favour of PROFIBUS DP (Decentralised Periphery) for most factory automation. Latest Kuhnke PROFIBUS Masters are all DP, 12Mbaud.
PROFIBUS & CANopen
PROFIBUS and CANopen are protocols used for connecting "local" intelligent devices and PLC's to a Master PLC. Connection is by a 2 wire shielded (or similar) infrastructure with the facility for very long cable runs. Essentially these are data exchange networks. If sensors and actuators require connection into such systems, then final hard wiring is required, and some degree of centralisation has to be designed in, for example bundling of 16 input & 16 output cable pairs to a PROFIBUS slave.
AS-Interface is a connection system for I/O which avoids the cable bundles mentioned here. AS-Interface (Actuator Sensor Interface) is nevertheless a bus system in it's own right. It can be stand alone, or be a subsystem to higher level buses such as PROFIBUS, CANopen, DEVICENET etc.
Kuhnke AS-Interface products include AIRBOX - a range of pneumatic devices, POWERBOX - a relay device, and a combined IPC/ASi Master.
Visit our dedicated website www.kuhnkeairbox.com for more information about AS-Interface and Kuhnke products. There are useful downloads including beginners guides.