To get the buck/Enhance function, all that is necessary is two separate switches so which the AC enter can be linked to one of the two Main faucets, though the load is linked to the opposite, So using the main transformer's Main windings being an autotransformer. This solution is for https://craftsy37147.nizarblog.com/33954701/uninterruptible-power-supply-calculator-can-be-fun-for-anyone