Oddly enough, I have yet to run into a Spanish-as-a-first-language electrician here in Southern Cali. I picked up most of my Spanish from masons, rockers, laborers, etc.
This means that, although I have very little Spanish to help in the electrical trade, I can however get kicked out of any Spanish speaking church in the world
I'm sure that if you take a class on Spanish, with a human instructor, you can inquire as to the specifics related to the electrical trade and the "way of things". I bet if you present specific questions, a competent instructor will find out what you need to know.