Research bench was developed for electrical machine tests basically in generator mode. It consists of two parts. The first part holds the drive DC motor, researched machine and DC motor drive module, the second part holds the measurement panel, voltage and current transformer block and load rheostats. While the drive motor runs the researchable machine, the measurement panel displays the amounts of four physical values: voltage, current, frequency and temperature. The main developments within this bench are: DC motor drive, which is single phase controlled rectifier; frequency counter and frequency counter based RMS voltmeter. The IC MC14553BCP is used as 3-decade counter/driver/multiplexer which is the simplification key in frequency counter circuits. As RMS detector in voltmeters IC LTC1966 is used, which gives low cost and high precision performance. The measurement transformer block allows measuring the voltage and current in three phases just by switching the phase selector.