My PSR3000 power supply has failed twice, in both cases it was the low voltage wire failing within 2 inches of the power supply brick. Once you have found the single screw beneath the Yamaha info sticker the supply comes apart quite easily. Chopping and resoldering the low voltage wire is then quite easy.

Thankfully both failures were indicated by intermittent connection when the wires moved so I never suffered a catastrophic sudden mid-gig power loss situation.