The EL3742 analog input terminal handles signals in the range between 0 and 20 mA. The voltage is digitised to a resolution of 16 bits, and is transmitted, electrically isolated, to the controller. The input channels of the EtherCAT Terminal have differential inputs and possess a common, internal ground potential. The signals are oversampled with an adjustable, integer multiple (oversampling factor: n) of the bus cycle frequency (n microcycles per bus cycle). For each bus cycle, the EtherCAT Terminal generates a process data block that is collected and transferred during the next bus cycle. The time base of the terminal can be synchronised precisely with other EtherCAT devices via distributed clocks. This procedure enables the temporal resolution of the analog input signals to be increased to n times the bus cycle time. In conjunction with the EL47xx (analog output terminal with oversampling), responses with equidistant time intervals, e.g. in the event of a threshold value being exceeded, become possible. The distributed clocks function enables several EL3742 devices to be synchronised in almost any configuration. The maximum sampling rate per channel is 100 ksamples/s (100,000 samples/s).

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