You need floor plans. You need panel schedules. You need to trace conduit paths.
Before we discuss the textbook, we must understand the domain. Commercial wiring differs from residential in five critical ways: You need floor plans
With a commercial electrical wiring textbook, you can expect to learn about: You need floor plans
You get the searchability of a PDF and the tactile utility of printed construction plans. That is a hard combo to beat. You need floor plans