3.16
Counting
3.16.1
Properties
Counting functions
The 8 DI NAMUR electronics module has configurable counting functions:
● 2 x 16-bit up counters (standard counting function) or
● 2 x 16-bit down counters (standard counting function) or
● 1 x 32-bit down counter (cascading counter function)
● Setting a setpoint with the POI
● GATE function
● You can configure the control signals of the counters:
– "2 Count/ 6DI NAMUR" configuration: Two counters are configured. The control signals
of the counters are stored in the POI (process output image).
– "2 Count/ 6 Control" configuration: Two counters are configured. The control signals of
the counters are stored in the POI (process output image). They are also controlled by
the digital inputs of the 8 DI NAMUR.
● You configure the counters of the 8 DI NAMUR electronic module and assign the
parameters in the engineering software, for example, HW Config.
3.16.2
Principle of operation
16-bit up counters (standard counting function)
The counting range is always 0 to 65,535.
With each count pulse at the digital input, the count is incremented by 1. Once the count limit
is reached, the counter is reset to 0 and it counts up again from this value.
If there is counter overflow, the corresponding output is set in the PII.
A positive edge of the
Reset output control signal resets the output in the PII. This does not
affect the current count value.
In 16-bit up counting operations, the system does not set any outputs in the POI. These are
always reset.
The positive edge of the
Reset counter control signal sets the counter to 0 and resets the set
counter output.
The
GATE control signal pauses the counting on a positive edge. Count pulses are processed
at the digital input again, but only at the negative edge. The
Reset counter control signal is
also effective when
GATE is active.
Configuration options
3.16 Counting
ET 200iSP
70
Operating Instructions, 11/2017, A5E00247483-07
