GK MB2-500 and protect mode fun

[Greevus]

Had my first venture into figuring out "protect mode". Bought my 2nd GK MB and had both running into two 4 ohm cabs, using a Y input cable.
2nd amp supposedly never had probs, but began going into PM almost immediately. So I began mixing and matching cabs, cables, etc and every combo did the same. Even my original MB did it and it never had before. I finally got a voltmeter and an outlet checker and everything seemed good in the jam room. So, went to check the 2nd MB again and for some reason I happened to notice the power cords on my two MB's were smaller diameter than the ones going to my SVT and 800RB. I also remembered that in anger I had switched power cords to test both MBs on the 2nd rehearsal of cutting out. I took the larger SVT cable and used it on the MB and it worked. I then noticed some noise/hum in the other MB head with the other smaller diameter cable. I took it out and used the 800RB power cord and fixed it again. Then I noticed both A/C cords were 18awg, but that the smaller ones were 250V and the larger were both 125V. What gives? I read through other threads and did searches, but nothing seemed to clarify. Why would the 125V larger cords work better? I realize my original cable could have some type of break or short, but what is the better choice?
I will admit scarce knowledge with electricity, but want to learn more.

[somegeezer]

Just use the original cables that came with the heads?

[Adam Bomb]

This is good to know, b/c some dude at Guitar Center once told me that all amp power cords were the same, and interchangeable.

Dudes at Guitar Center say a lot of things.

--Bomb

[jelwood]

I'm assuming larger means thicker? If so the larger cables were of higher gauge and are designed to carry higher currents, since higher currents are typically associated with more professional applications, the larger cables might be of better build quality as well. It could have been possible that in the smaller cable(s) they actually melted and created a short if you were running them before with higher powered appliances.

[B-string]

The wire gauge is what to look for, the voltage on the cord is not so important. All cords should be rated for at least 600volts break down. The larger cords are most likely larger gauge (lower gauge number= larger wire size).

[Greevus]

all 4 power cords were 18 gauge. the larger diameter (thicker) ones had 10 amp/125 volt on the female ends, the smaller diameter ones had 10 amp/250volts. The smaller ones were the ones that came with both MB2-500 heads. I found it very strange. that's why i was asking what was the real advantage of one over the other? what gauge is recommended? i can't find anything concrete. i used GK400RBs for about 15 years, and the power cords weren't removable.

[B-string]

The thicker ones may have twine in the jacket for reinforcement. A 10amp cord is a 10 amp cord. I prefer 16 or 14awg.