The power supply for my pool cleaner (Maytronics Dolphin Diagnostic) blows fuses. This is a basic power supply that converts 110VAC to 24VDC (150W). I opened it up and see nothing obvious with wiring or blown capacitors. I'm thinking the transformer (120VAC to 19.2VAC) has shorted some windings. If so, how do I test it and where would I find a replacement? The fuse is on the hot leg of the 120V input.