The AC500-eCo processor modules with onboard I/Os provide some special functionality on the digital inputs or digital outputs. Fast counter, encoder inputs, interrupt inputs or PWM/PTO outputs are available depending on the device used.

The fast counter functionality can be activated within the onboard I/O configuration.

The fast counter can work in pulse/direction mode or A/B track counter mode.

⮫ Further information about the operating modes of the fast counter

⮫ Further information about the configuration of the fast counter

As AC500-eCo PLCs provide the fast counters via their onboard I/Os not only the correct power distribution to the PLC has to be made, but also the correct wiring to the signal wires. How to connect and use fast counters in AC500-eCo PLCs is described in an ‎⮫ application example.

The pulse/direction counter detects the rising edge of the counter input. It will increase or decrease the count value (depending on the direction input) at every rising edge.

The A/B track counter is used to count the signal from an encoder.

The counter can count with quad phases. In the following the behavior of the A/B track counter is described.