This page contains the schematics of the K40 Power Supply Unit (PSU) so you can repair the power supply when it goes bang.
Most common part that breaks is the 24V low voltage Schottky diode MUR460. This shows as a short across the anode and cathode of the diode. Note: the PSU can only deliver 1A across 24V DC and when shorted, the Schottky diode blows. You cannot replace this with a common diode since these are too slow.
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