The EL3121 analog input terminal processes signals in the range between 4 and 20 mA. The current is digitised to a resolution of 16 bits and is transmitted, electrically isolated, to the higher-level automation device. The input channels of the EtherCAT Terminal have differential inputs and possess a common, internal ground potential. The EL3121 is the single-channel version and is characterised by its fine granularity and electrical isolation. An open lead or overload condition are detected. The terminal status is relayed to the controller via the E-bus. The EtherCAT Terminal indicates its signal state by means of light emitting diodes. The error LEDs indicate an overload condition and a broken wire.

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