Hello all, I'm assuming this will be a very simple answer, however since I don't have a strong background in electrical theory I am fairly baffled. I take care of the majority of repairs at a small live event company, and recently we had a medium sized 10,000 lumen projector die. After digging in to check fuses I saw that the 110V-230V selector switch was cooked after someone repeatedly toggled it while the unit was on. This switch is housed in a module along with the IEC Power Input and on off rocker switch. Apologies for not having a schematic, but there was surprisingly little going on. Both the hot and neutral of the IEC passed through the rocker switch where the neutral then passes through a ferrite core and out to a binding post. The hot leg then leads to 2 fuses, one rated 20A and the other 15A. These two fuses feed the two 'outputs' of the voltage selector switch, while the common then runs through the other side of the ferrite core and out to its own binding post. Once the voltage selector switch cooked, all three legs contacts were shorted no matter its position. I made my way through the circuit with a meter and had 120V until I hit the binding post, at which point it dropped down to an unstable 8V-9V. In order to get the unit operational again until replacement parts can come in, I replaced the voltage selector switch with a simple jumper on the 20A fused side, and we're back to 120V on the binding post. This brought up a few questions for me, the first being, why did a parallel path of 120V drop down to 8V, or was I just getting a noisy reading from my meter? I also thought that it was curious that the voltage selection switch was only used to select a more appropriately sized fuse, and not changing the path through the windings of a transformer. Is this a fairly common design choice in PSU's? Thanks for any insight, I am always trying to learn more about the physics behind power.