Abstract:In the generator monitor system, voltage and current transducer are used widely for monitoring the terminal voltage and current of the generator. Now in domestic market, the input signal frequency of AC transducer is limited to 45Hz to 55Hz. When the generator is in starting stage, the ordinary transducer cannot measure the low frequency voltage and current of generator. This paper designed a transducer which can measure true RMS of the terminal voltage and current of generator. This transducer converts input signal into DC signal by magnetic balance Holzer current transformer and AD536 chip. This transducer can measure 0~2000Hz voltage and current signals, which can measure both AC and DC input signals. This transducer effectively solves the problem of measuring the low frequency voltage and current of generator at start-up stage.