Display instrument for control element operational states - incorporates counters measuring on and off states of input signals

摘要

The invention relates to a display instrument which can monitor automatically the operational state of a control element e.g. a magnetic valve and display it in the form of a time diagram on e.g. a C.R.T. display. Input signals representing the individual operating conditions of the element are received by a counter controlled by a stroke generator whereby the counter registers the duration of one of the on/off conditions of the signal. A storage arrangement stores the span of time between a reference point for the start of operation and a change in status from on to off or vice versa.