The article covers examination of mathematical criteria that allow considering the process of testing the logical control systems at the stage of developing a control program as completed. Two mathematical approaches for detecting errors in software, i.e. the criterion for the intensity of error detection and the criterion for a given value of mean time to failure have been considered. An example of the calculation of mathematical criteria for a real task, i.e. testing the logical control program of the turret block of the electrical automation system of a machining center of oblique layout with CNC has been given. A variant of calculating the required test time to achieve the required value of time to failure has been given. It has been concluded that in order to increase the efficiency of testing, its acceleration and reduce the cost of testing, both for manual and automated testing methods, it is necessary to use methods and tools that allow eliminating the influence of the shortcomings of traditional approaches to testing.