Circuit arrangement, and level converter and comparator circuit for the circuit arrangement

The device has phase conductors (L1-L3) which are connected to level converters (PW1,PW2) whose outputs are connected to voltage detection input (A-D) of microcontroller (MC) and input of monitoring module. Microcontroller outputs pulse width modulated signal (PWM2) to each phase conductor, whose duty cycle depends voltage value of voltage detection input. A voltage comparator (V) compares voltage levels of input terminals (VE1,VE2), depends on voltage value of digital de-energizing signal output of logic modules (V1,V2) to control controlled circuit breaker (R2). An independent claim is included for level transducer for circuit device.