DC generators with integrated AMF feature for On/Off-grid applications are -48Vdc power modules ready to provide standby power to any Telecom site.  
Moreover this range of products manages DC/AC inputs (solar/wind/grid) without modifications, eliminating the need for an external ATS.
The Ascot DC genset with AMF is the best solution for On-grid back up, Full Solar system back up and it is even applicable for Off-grid site as primary source of power running 24/7.