Hello! I changed the transformer of a car battery charger that burned. It had a transformer with two inputs and two outputs rectified to measure wave. I exchanged it for a larger UPS (more than double - physical size), it has a midpoint and I rectified it at full wave with a positive midpoint as it worked in the UPS. This transformer has 5 wires at the input: blue (common), orange, white, yellow and brown. Use blue and orange to obtain 13.8Vac at any of the two outputs and the midpoint, and 11.7Vdc after rectifying with diodes 6a10 ... I understand that this rectified voltage serves because what it loads is the peak voltage. .. I would like to know if I can install a selector key to switch from Blue / Orange to Blue / White and get 15.7Vac in the outputs for fast charging in case of any trouble ... Note: I have it armed without the selector but I haven't tried it yet to load.