Effective October 1, 2023, the examinations will be referenced to the
2023 NEC Code Book
Get to know chapter 2 for the Texas PSI exam
Texas PSI Exam seminar sneak peek. Click here to learn more about our seminars. There are some sections of chapter 2 that you will run across on in the exam. You’ll also have some smaller sections that we are not going to focus on today because they account for less than 2 questions out of 100.
Here are the most important Articles in Chapter 2:
210...Branch Circuit Rules & Requirements.
225...Outside Circuits and Feeders.
Texas PSI Exam Prep - Chapter 2 Review
I guarantee that you will see the sections I will be talking about next on your exam, so write this stuff down. Make sure to highlight these articles in the table of contents of your NEC. Don't forget to highlight the actual articles inside the book as well because you will need them!
Article 210 branch circuit rules and requirements
We use a couple of examples of this in the seminar. There are questions on two small appliance loads required. You have one that asks about laundry load that requires a branch circuit. And one about branch circuit for every bathroom that's included in the house. Those are the things that you'll find here in this article.
You'll also find the rules for GFCI installation. What areas have to have GFCIs etc. Article 210.8 and 210.19 which is your arc fault rules and requirements.
Article 215 is your feeders.
Article 220 Calculations
This article is specific calculations. The test is very heavy on article 220. You've got to know article 220 very well. In the seminar we go through it a lot. You’ll leave the seminar with 220 oozing out of your ears. But don't worry because this will actually be useful for you. It is a good tool to know for your trade.
Article 225 Outside Circuits and Feeders
Article 230 Services
Oftentimes you'll see test questions that have references to both Articles 225 and 230. This question is a two-part lookup question where you have to look up an outside service issue. So you’ll have to refer to both articles in order to answer that question.
Article 240 OCPD (Breakers/Fuses)
In article 240 is your overcurrent protective devices. That’s your breaker, circuit breaker and fuses.
Article 250 Grounding
You are going to have quite a few grounding questions. The separately derived system category in the PSI candidate bulletin that actually has a lot to do with grounding.
You'll see separately derived system grounding rules and procedures set out and stipulated.
Texas PSI Exam Side Notes
What is a separately derived system? It is a service that is separated from another service and has to, by its own definition, have its own grounding and bonding rule because it is separated from another service.
A transformer is a perfect example of a separately derived system.
When you transform a voltage class from 480 down to 240 volt you're taking two windings, two coals. You've got your two windings that are separated around a core and that inductive reactance between the primary side and the secondary side is what causes that voltage to step down.
Well, that's physically separated from each other. There are no mechanical connections between the two. So, if you have the primary side bonded and grounded properly, but you don't have the secondary side bonded and grounded properly - somebody could get hurt.
Those are two separately derived services so you must have rules for both of those.
A generator is a great example of a separately derived system because it is a generator of electricity that's not connected physically to the primary side.
Most of the rules that you see for separately drive systems are going to be grounded and bonding.