FIELD: testing and diagnostics of automatic control systems and their units. SUBSTANCE: method comprises steps of determining nominal parameters of diagnostical model of unit; determining gain value of damaged unit; determining time constant of said unit; determining nominal value of time constant of said unit; determining nominal value of gain of unit; changing normal unit by damaged one; determining values of gain and time constant for each tested unit at constant setting values; determining fluctuation of time constant value from nominal one for each tested unit; determining fluctuation of gain value from nominal one for each tested unit. Apparatus for performing the method includes driving circuit, unit for forming pulse signal, circuit for latching maximum value of said signal, tested unit, first division unit, first adder, first amplifier, second amplifier, first circuit for controlling tolerance, second amplifier, third adder, second circuit for controlling tolerance, third amplifier. EFFECT: enlarged possibilities of method for testing parameters of dynamic systems, simplified process of parameter testing. 2 cl, 7 dwg
