Festo VMPA-FB-PS Series, Руководство пользователя

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2. MPA pressure sensor
2−10
Festo P.BE−MPA−ELECTRONIC−EN en 0804NH
Module parameter: Hysteresis Handheld
Function no. Hysteresis: m = module number (1 ... 47)
4828 + m * 64 + 13 (Low Byte)
4828 + m * 64 + 14 (High Byte)
Description This parameter defines the hysteresis behaviour of the pressure diagnosis
(see following section). The data format is described in Tab.2/10.
Bit Bit 0 ... 7: High byte or low byte of the hysteresis [Hysteresis]
Values Default setting: Hysteresis = 0 (Low Byte = 0; High Byte: 0)
Minimum value:
0
Maximum value: Upper limit value − lower limit value
Note The defined hysteresis value may not be larger than the difference between
the upper and lower limit values.
The hysteresis value is not checked for validity during parameterisation!
Unsuitable parameterisations are adopted in this case the module can react
unexpectedly. Check the parameterisation!
If Monitoring of parameterisation faults" module parameter is active, then a
corresponding fault is signaled. Tab.2/3 shows the possible parameterisation
faults.
Tab.2/9: Setting hysteresis
Hysteresis behaviour
If hysteresis is defined, then the MPA pressure sensor be
haves as follows (see also Fig.2/1):
The measured value must be less than the lower limit
value minus the hysteresis before a diagnostic signal
occurs .
The measured value must be greater than the upper limit
value plus the hysteresis before a diagnostic signal
occurs .
The hysteresis behaviour provides you with more flexibility in
setting the limit values.