Endress+Hauser ASP Station 2000 peristaltic, Руководство по эксплуатации

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Commissioning ASP station 2000 peristaltic
102 Hauser
2 modes are available to the user for time switching:
• Choice day:
Switch to the switching programme at two settable times in one day.
• Choice week:
Switch to the switching programme at three settable days (incl. time) in the week.
Switching via external signal
Fig. 44: Switching via external signal
The switch to the switching programme takes place via an external digital signal which is present
at one of the digital inputs.
"
Caution!
For this function, the corresponding digital input must be configured with the SWITCH function.
Switching based on a measured flow
Fig. 45: Example: switching based on a measured flow
In this option, the switch to the switching programme takes place on the basis of a flow measured
at the analogue input.
In this switching criterion, both an upper and a lower limit value can be defined for the switch. This
makes it possible to define a range in which the main programme is active. If you leave the
configured range, the switching programme is activated immediately. If only an upper or a lower
limit value should be monitored, the other limit value is deactivated.
The limit values are assigned to an adjustable hysteresis. In other words, the measured flow has to
return to the specific range by the amount of the hysteresis before the system switches back to the
main programme.
For example, in the settings in
→
Fig. 45, the system switches to the switching programme at a
measured flow of 200 l/s. However, the system switches back to the main programme at a
measured flow of 190 l/s. For the lower limit value, the system switches to the switching
programme at 100 l/s and switches back to the main programme at 110 l/s.
"
Caution!
A quantity signal has to be connected to the analogue input of the controller for this function.