There are a lot of ways to easily miss some electrical exam questions due to some confusing tables and calculations. Here are some of our top tips on conduit fill, residential dwellings, electric range and 3-phase tips on answering this types of questions.
With conduit fill we are concerned with protecting the physical properties of the wire itself, and we count EVERY wire. When dealing with sizing wire for ampacity, we are concerned with the heat generated from the current flow, and the insulation that protects it. Because some wires are not current carrying conductors, we don't count every wire when derating.
When calculating residential dwellings, something thing to keep in the front of your mind: is which portions of the building are included in the square footage lighting load calculation, and which portions are excluded specifically according to the NEC®.
T220.55 Electric Range
Electric Range table, T220.55 is one of the toughest tables in the entire book to understand and master. Here is a hint - read the notes below the table.
The biggest error that most test takers make is when calculating a three phase formula. A three phase system must have the voltage multiplied times a factor of 1.73. Without getting into heavy math or complex electrical theory; three-phase voltages must be multiplied by 1.73 at all times.
Don’t forget to check out our live seminars if you are taking the Texas electrical exam. We go over these and many other subject categories to prepare you for the journeyman electrical exam and master electrical exam.
Thanks for reading & good luck!