Melted power cable.

[currly30]

I went to upgrade the caps on my Kaiju and I noticed that the neutral part of the power cable was partially melted.
Also the neutral terminal on the back of the IEC looked corroded/oxidized. There doesn't seem to be any signs of damage on the IEC itself.
I plugged in a new power cord and tested all the points the manual has you test and everything was with in the normal range.
Any ideas on what could be causing this?

 

[currly30]

The amp was working fine with no issues or noise.

I haven't tried running music through it since noticing the issue and retesting the voltages.

 

[Paul Birkeland]

Loose pin fitment could certainly cause that.  The Kaiju draws relatively little power relative to what a cord like that can provide, so I would not suspect that there's any kind of operational issue causing excessive current draw.  If debris got in there and didn't allow for a tight fit, you could also end up with that issue.

 

[Doc B]

It's possible that, although the joint looks very well formed, there is excess flux on the neutral pin on the IEC socket. I'd be inclined to reflow that joint and to use a new power cord. Check the wire that is soldered to that neutral pin at its other end too.

 

[currly30]

The stock power cord no longer works in the Kaiju. When I tried plugging it back in, after noticing the damage and reflowing the joint, there was no power going to the amp. The Kaiju works if I use a different power cable.

 

[currly30]

Hey, I took some pictures of the top of the IEC before I cleaned it up. It also looked like the solder point, it had the yellow brown discoloration on it. After cleaning it up I noticed little weld spots on the post and the pin is a little smaller with exposed copper on it. What would have caused the little spots on it and the melting away of the outside? Should I be concerned about them?

 

[Paul Birkeland]

That could just be really bad pin fitment, like a loose contact in the power cord itself or a little debris in the power cord.  If the replacement cord is making good contact, I wouldn't be super worried about that.

 

[currly30]

the stock cord doesn't work for anything now. I used a different cord when I first built the amp to test it and it had no problems. So I'm guessing the stock cord wasn't built properly and is what caused the problem.