PowerEdge R7525 power supply looks to have exploded

I heard a large thud and the PDU breaker tripped. The house breaker might for the circuit might have tripped as well (can't remember in my scrambling's to find out what happened).

I disconnected power and pulled the 01CW9G 1400W power supply. Diagnostic lights are all out. No orange or green light on handle when connected. Since support staff were busy on chat I ended up opening the power supply to look inside. It's burnt near the input side. See picture.

What I am trying to understand is if this would be a way a faulty power supply would fail or if this is likely caused by a fault in the server drawing too much power. Thanks.

Neill.