In my barn, I have a box that has a big switch at has: on for electrical coming in from the line, off, and on for generator. For generator use, it has a big cord with a large 3 prong welding cord plug that plugged into the generator. It was set up years ago to use with a generator that ran by hooking it up to a tractor PTO. I no longer have this tractor powered generator. Could I use a 3 prong welder plug to standard 30 amp plug adapter to use my standard 4000w gas powered generator if we have a power outage? I would only use it a short time to be able to run the well and lights for a short time to water and feed the horses.