Yesterday, the strangest thing happened.  I hooked up Mr. Brightside (my 250w GE Mercury NEMA) and it shut down after 3 seconds.  I changed it back to my 100w HPS and it still didn't turn on.  I was dumbfounded and I eventually changed out the cord, and it worked.  It is amazing that a cord went bad.  Has anyone else had this happen?

In my experience no standard cords or wires used for experimenting (so connecting and disconnecting very frequently) survive longer than a year or so.

So I don't think it is so much unusual...

There are special wires designed for such manipulation (soft silicone or similar insulation, a lot of very hin wires as conductors, elaborate strain relief in connectors), but these tend to be quite expensive, so I just have spare wires and do not expect any long life with them...

Nope never had a cord fail, and i tend to scavenge them from already thrown out items so they've seen a good bit of use AS IS, they usually are reliable as far as i can tell

In my experience no standard cords or wires used for experimenting (so connecting and disconnecting very frequently) survive longer than a year or so.

So I don't think it is so much unusual...

There are special wires designed for such manipulation (soft silicone or similar insulation, a lot of very hin wires as conductors, elaborate strain relief in connectors), but these tend to be quite expensive, so I just have spare wires and do not expect any long life with them...

I have wires like that in the test leads of my multimeter. They are high quality, Fluke made wires. See lot of abuse. One already failed open circuit. I repaired it for now (solder and shrink wrap), but i dont know how many more bad places are elsewhere, so for now im carefull not to use it for verification that a circuit is not energized, and not to use it as amp meter at any significant currents. Gotta replace the leads soon

In power leads, i had few that failed. All of them without any significant use, it allways came down to being of bad quality in the 1st place. A good lead will be fine for years, and if it is abused, it will visibly look bad (worn isolation, not round anymore where the inner wires were bent) long before it actually fails

Wanted to light my Wide -Lite 450W PSMH-all I got was a Flicker when plugged in.Just tightened the cord connections in the plug-then lit just fine!MH BLISS-an old Michlen Tire Co high bay ceiling lamp.From their plant in Wilson,NC.

I acquired a well used NEMA head that was not used anymore since they couldn't get it to light. They tried a couple of lamps, a couple of photocells, still nothing. I got the same results. There was a piece of outdoor rated romex attached to it. I got rid of that and plugged the ballast directly in an extension cord. It works quite well now despite a rusty ballast.

Before leaving for a recent vacation, I switched off most electronic-containing appliances (kitchen stove, microwave oven, washer/dryer, dishwasher, etc) in case of power surges. The 4-month old dishwasher wouldn't power up after I reset the breaker. There is a terminal block in a junction box under the kitchen sink, and the screws were loose. What a relief it was fixed.

lol i found the same situation with the NEMA i had found, the wires were kindof gooey though, probably because they had been sitting in the back of a car n the junkyard for i don't know how long,