The unique innovative VTS (Voltage Transfer Switch) phase switching system allows the generator to be used in both three-phase mode (400 V) and single-phase mode (230 V) without loss of power! It is no longer necessary to purchase and maintain two separate generators: simply switch the mode and set the "Könner & Söhnen" generator to the required voltage with the phase switching system. VTS SYSTEM With the unique, innovative phase switching system VTS (Voltage Transfer Switch), the generator can be used in both three-phase operation (380V) and single-phase operation (230V) without loss of power. There is no need to purchase, store, operate and transport multiple generators to the property. You can simply switch the working mode and use the “Könner&Söhnen” generator with the phase switching.