PLC/HMI connection: signals, alarms & intervals
The connection to PLC/HMI increases process reliability and transparency. Here are the tried and tested signals, alarms and strategies for interval control.
Recommended signals
- Digital: Total fault, operation/enable, min. level, pressure switch
- Analogue: Pressure, flow, temperature (optional)
- Counting pulses: Stroke sensor progressive distributor
Alarm & notification concept
- OK/Warning/Alarm per measured value with defined limit values
- Time window: Start/stop phases and acknowledgment
- Error texts: clear & user-friendly on the HMI
Interval strategies
- Fixed interval (time/distance dependent) with adjustment to load/temperature
- Conditional triggering (when process active / thresholds reached)
- Trend-based optimization: quantity correction depending on wear indicators
Documentation & traceability
- History for pressure/stroke/flow with time stamp
- Log maintenance events, refills & filter changes
- Export (CSV/PDF) for QA/Service
More: Control & monitoring · Central lubrication · Advice
FAQ
Which cycle dates are mandatory?
Pressure curve, stroke pulses (for progressive), fault and acknowledgment events.
Do I need analog sensors?
Yes recommended for trend/early detection; purely binary works, but provides less depth.