SITOP PSU100C Power Supplies Siemens SITOP PSU100C Power Supplies feature a slim line design for distributed applications. SITOP PSU100C offers a 22.5mm to 52.5mm width, requiring up to one-third less space on the mounting rail than comparable devices. These 12V and 24V Siemens power supplies offer high efficiency across the entire load range. Power loss is extremely low, even during no-load operation. This makes the power supplies ideal for efficiently supplying machinery and equipment that are often in standby mode. PSU100C can save up to 35% of energy.