StrG controller is destined to work with stepper motor controllers which are controlled by three signals STEP, DIR, ENABLED e.g. StrK. This device consists of a internal rectifier and a voltage regulator with output 30V +/-10% and a current 1.5A. Additionally, StrG has got security and alarm circuit, which I case of alarm signal (open security circuit) switches off power supply and reports alarm. Moreover the controller consists two relay output to use for control one phase devices (230V 3A) such us pomp, blower, motor. It is possible to track device by means of LED indicators placed on front of a box. StrG could be mounted on 35mm rail. Power supply and inputs/outputs are isolated, what helps to better protect device and connected PC computer. Using StrG plus three StrK, we can easily build three axis CNC machine. The controller is adjust to direct connect to LPT port and collaborate w Mach2(3) software.