The multifunction transducer must have two sets of inputs, a voltage input that has to be matched to the electricity supply voltage of the starter and a current input that has to match the full load current of the motor.
Where the electricity supply voltage is above low voltage then the transducer must be powered via a potential transformer with a secondary voltage of 110V it must also have an accuracy class of 0.5 or better and an output of 50VA.
Where the electricity supply is at low voltage the transducer should have a wide range of voltage input to accept any voltage.
The current input must be derived from current transformers with 5A secondaries and an accuracy class of 0.5 or better. The transducer burden on the current transformers should not exceed 1VA and the current transformer to transducer cables should have a burden on the current transformer that does not exceed 1.5VA. This permits the use of current transformers with an output of 2.5VA.
The transducer should have an accuracy class of 0.2 (IEC 688) over the range of 10-120% of the nominal inputs. It must have internal PT and CT ratio settings and should measure phase to phase voltages, line currents, kW, kVA, kVAr, overall power factor, kWhrs, kVAhrs and kVArhrs the energy registers should be non-volatile. It should have RS485 interface to enable it to be connected to the SCADA system with a baud rate of 19200.