The EL3311 analog input terminal allows thermocouples to be connected directly. The EtherCAT Terminal's circuit can operate thermocouple sensors using the 2-wire technique. Linearisation over the full temperature range is realised with the aid of a microprocessor. The temperature range can be selected freely. The error LEDs indicate a broken wire. Compensation for the cold junction is made through an internal temperature measurement at the terminal. The EL3311 can also be used for mV measurement.

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