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1. A DC meter for an electrical vehicle charging station having a pair of DC power supply lines extending from a charging station controller to an electrical vehicle connector, the DC meter comprising a meter unit and a sensor unit, the meter unit comprising a user interface, a sensor interface for connection to the sensor unit, a metering interface for connection to the charging station controller, and a microprocessor configured to receive and process signals received from the sensor unit, to exchange data with the charging station controller and to receive commands from the user interface and output information to the user interface, wherein the sensor unit is separate from the meter unit and connected at a point distal from the meter unit via an interconnection cable for the transmission of measurement signals, the sensor unit comprising a current sensor coupled to one of the pair of DC power supply lines and configured for measuring the current flowing through said power line, the sensor unit further comprising a voltage sensor for coupling to each of the pair of power supply lines for measuring a voltage difference therebetween, the sensor unit further comprising a microprocessor with analog to digital convertors (ADC) for converting received analog voltage measurement and current measurement signals to digital signals, the sensor unit further comprising a communication interface configured for transmission of encrypted data through the interconnection cable to the meter unit, wherein the voltage sensor comprises a connector coupled to voltage sensor cables having connection ends distal from the sensor unit for connection to the DC power supply lines at or proximate the electrical vehicle connector, wherein the sensor unit comprises a connector for the voltage sensor cables and a connector for the communication interface for connection to the interconnection cable.
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