Eaton easy800

9 Inside 800
Control Relay easy800 11/11 MN04902001Z-EN www.eaton.com 317
9 Inside 800
In conventional control systems, a relay or contactor control processes all the
rungs in parallel. The speed with which a contactor switches is thus
dependent on the components used, and ranges from 15 to 40 ms for relay
pick-up and drop-out.
With easy800 the circuit diagram is processed with a microprocessor that
simulates the contacts and relays of the circuit concerned and thus
processes all switching operations considerably faster. Depending on its
size, the circuit diagram is processed cyclically every 0.1 to 40 ms.
Figure 208:Cycle timeeasy800
a Read process image
– Local inputs
– Function block inputs
–Markers
– Diagnostics information
– NET stations inputs
– SWD input operands
b Process circuit diagram and function block diagram
c Write process image
– Local outputs
– Function block outputs
–Markers
– NET stations outputs
– SWD output operands
During this time, the easy800 device passes through six segments in
succession.
If the operands of the inputs and outputs are addressed in the easy800, the
signal states of the digital inputs/outputs are not scanned but a memory
range in the device system memory is accessed. This memory range is
called the process image. The process image is divided into two sections:
the process image for the inputs and the process image for the outputs.
①
②
③