14
Festo — MSE6-E2M — 2022-08d
Functions
1
2
3
4
5
Fig. 5: Block diagram of the “Pressure” function
1
Unit pressure parameter
2
Upper limit pressure parameter
3
Diagnostics limit values startup parameter
4
Diagnostics limit values parameter
5
Parameterisation diagnostics errors param-
eter
5.1.4
Pressure change
5.1.4.1
Measurement method
The pressure change DP2 is determined cyclically at intervals of the parameterisable pressure change
sample time DT. When calculating the pressure change, the difference between the current measured
pressure value and the measured pressure value DT, based on the pressure change sample time P2, is
calculated: DP2 = P2(t) – P2(t-DT); t = current measuring point.
The start of the measuring cycle to calculate the pressure change is automatically synchronised with
the activation signal of the shut-off valve. The current pressure change value DP2 remains constant
up to the next measuring time. Every time the unit, Pm.8, parameter is written, a re-synchronisation
follows.
In the blocking state, the amount of the pressure change value is compared to the upper pressure
change critical limit DP2_OGR and monitored to determine whether the critical limit has been
exceeded. Once critical limit monitoring is activated, a diagnostic message is generated if the param-
eter ABS(DP2) is
>
DP2_OGR. Information on the resolution of the pressure measurement range
