I will use my own experience as a general guide so you can do your own version. After having struggled with all kinds of equipment my entire life, ranging from farming machinery, light industry power tools with a diverse degree of complexity, my best advice is:
Don't. Lose. The. Operation. Manual.
It doesn't matter if it is written in Chinglish. It could have important numbers, or perhaps even calculations, equations, wiring diagrams (extremely important) and using them may prevent a failure with potentially harmful consequences.
I am confident that most readers are moderately educated and careful people. However, I have acquired some useful habits like dedicating a special file just for user manuals and handbooks, something that I am sure many of you already have, as a prepper.
By reading seemingly small amounts of evident information, I learned that a simple venting fan for my bathroom could set itself on fire if a piece was wired incorrectly, for instance. So manuals are important for every kind of device, no matter how simple it may appear.
Each manufacturer is forced by law to inform the weaknesses of their products, and this is important. You don't need an engineering degree; most of the time it is very simple to know if some equipment is going to be damaged or generate a potentially harmful situation.
That said, once I had most of my equipment to be used after a potential event, I prepared some coffee, and planted myself at the dining room table with all the manuals of the equipment that used electricity.
Grab a notebook – getting prepared ahead of time
In a notebook, I wrote all the standard and maximum loads for every machine. The manual usually shows this inside parenthesis or similar signs: ( ) We all know that all of our equipment is not going to work at max load at the same time, of course, but this is going to be needed. Perhaps we are working with, say, our bench drill in the workshop, with our fan on, and the refrigerator kicks in, while we are in the middle of the summer and the baby is peacefully sleeping in a room with A/C…and there is an overload that makes a mess of our day. See my point?