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Intelligent data acquisition key features:
- Online evaluation of measurement data, executed immediately after each done sample
- Multiplexed and parallel synchronized sampling
- Complex triggering conditions, high sampling rates
- Online measurement data processing and data reduction
- Free programmable mathematical operations: statistics, RMS, min/max, mean, integral, derivation, correlation, digital filters, FFT, signal analysis, etc.
- Angular synchronous data acquisition and analysis
- True RMS online calculation
- High speed data acquisition (up to the megahertz range) with boundary curve evaluation with alarm functions
- Detection of signal interruptions (peaks) on relays, switches, connectors, boards, during environmental and endurance tests, closed contact monitoring and analysis
- Statistic online evaluation of particles in a stream of gas, fluids, etc.
- Up to 120 parallel channels or 480 multiplexed channels, more via parallel ADwin systems
Simple trigger conditions, as they are typically used for passive boards, are based on rising or falling signals vs. a static threshold or a digital signal on a trigger input. ADwin real-time systems provide much more, intelligent and complex trigger conditions.
Generally speaking, intelligent or complex trigger conditions are based on results of a combination of events and parameters of measurement signals. The ADwin system allows the user to program any mathematical online operations in every sampling step. Therefore, it its possible to set the results into any logic-mathematical relation, so each measurement value can be checked if the required trigger conditions have been reached. As a consequence, only those measurement data with information are acquiredp; the rest are rejected. Therefore, an intelligent trigger condition also produces a powerful data reduction during the measurement data acquisition. Even with high sampling rates in the range of megahertz, it is possible to acquire data for hours, days and weeks.
Here are some examples of intelligent and complex tríggers:
- A simple trigger function is checking a set of digital inputs lines. Measurement data will be acquired only if a defined bit pattern is provided.
- A more complex trigger function at digital inputs could be the evaluation of a chronological sequence of digital pattern; only a valid sequence would force a trigger.
- A trigger based on analog input values, only if the RMS value (root-mean-square) is over a limit, or rises over a threshold, or falls below a threshold, or the RMS value of a single peak has a certain minimum, or ...
- Triggers forced by shaft encoder sensor at a rotating shaft. Only if the shaft angle is in a defined sector, an angle-based data acquisition is executed, or data should be collected during N rotations, or this can be combined with an angle-based online analysis, ...
- Another application is to monitor messages on a CAN bus, Profibus, or Interbus. Only at the moment when certain messages arrive, measurement data should be collected with a pre- or post-trigger.
- Others are easily programmable—just define your intelligent triggering in the real-time development tool, ADbasic
It does not matter how a trigger event is defined, it is always possible to acquire data in a certain time interval before the trigger (pre-trigger) or after the trigger occurred (post-trigger). Be sure to take into account that measurement data can be acquired ranging from hundreds of hertz to millions of hertz. As you can see, there are no limits to the ways in which intelligent and complex trigger functions can be defined.
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