(Don't do this) Adapting regular extension cords to PV

[sowbug]

Disclaimer: this is a bad idea. Don't do it.

This weekend I needed a very long pair of MC4 cables to test a system at home. I didn't feel like paying $140 to buy 500 feet of 10AWG THHN at Home Depot, but I did have lots of heavy-duty extension cords, as all of us do. I also had a bunch of MC4 connectors. I decided to build a pair of adapters to temporarily turn a regular NEMA 5-15 extension cord into an MC4 extension cable.



You can see what I did from this picture. I tried to make the wires mean the same thing (negative is ground/green, also tied to neutral/white, and positive is hot/black).

I'm still alive. It worked great, and now I have two weird adapters that I can use to hack extension cords into a PV cable when I don't have one that's long enough.

Obviously this is dangerous. If I left one of these adapters on either end, then the resulting cable would tell terrible lies to whoever encountered it, and someone (including future me) might plug it in and get bad results.

But it worked, and it saved me from buying an expensive MC4 cable set.

 

[Brett V]

Adapt, Improvise, Overcome. Well done!

 

[Hedges]

I have a plastic reel with 12/2 UF coiled on it, and MC3 pigtails at each end. Safety switch at one end for disconnect. I've used that to bring PV leads into my workshop.

I plan for metal conduit into my new lab setup so it is hard wired.

I think you should keep the green wire separate and use it to ground PV panel frames back to inverter. Those often become a shock hazard otherwise.

On the bright side, yours aren't a suicide cord; they are touch safe.
And in a pinch you can power tools with universal motors by DC. No guarantee the switch will hold up.