Inability to adjust the QRS Maximum manually in the Averaging View is expected behavior in Chart/LabChart. The QRS Maximum is used to identify each ECG event and define all of the associated parameters (P wave, T wave, QRS start, etc.) in the ECG Analysis algorithm. Because of this dependence in the rest of the algorithm, it cannot be manually adjusted in the Averaging View like other ECG parameters. If the QRS Maximum is being identified incorrectly, you can correct this by adjusting the ECG Analysis Module detection settings (ECG Analysis Menu -> Setting...).
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