Electricians are fundamental to any construction project, responsible for the installation and repair of all necessary electrical wiring systems. Their role extends to inspecting and maintaining existing electrical infrastructures, such as lighting and intercom systems, to assess their longevity and safety in relation to the overall construction.

If you're heading into an electrician interview, be ready for more than basic questions. Employers want to know how you troubleshoot in the field, how well you know safety protocols, and whether you can read a blueprint as easily as you use a multimeter. The following questions will help you prepare thoughtful, experience-backed answers that show you're ready to get to work.

Electrician Interview Questions

1. What got you interested in the electrical trade?

This is a general opening question in which the interviewer will ask you to begin the conversation, learn more about your background, and discover some information they can use for additional questions.

Example Answer

"I have always had a fascination with science and technology. From an early age, I was curious about how things work, especially electronic devices. This interest developed further when I learned math and science principles and could better understand the theory behind electricity. During summers in high school, I worked with a friend's father, who was an electrician. He taught me quite a bit and encouraged me to pursue a career in this field."

2. Can you describe the difference between a breaker and a fuse for me?

This is a technical question. When interviewing for a job as an electrician, you can anticipate that the majority of questions will be technical or operational. The best way to answer technical questions is directly and concisely.

Example Answer

"Breakers and fuses are both devices meant to interrupt the flow of electrical current. The difference is a fuse can only function once because it destroys itself when it interrupts the current. Breakers are like switches and can be reset. Fuses are no longer used in construction and can only be found in electrical devices or vehicles."

3. What is your process for finishing a job and making sure it meets the specifications?

This is an operational question. Operational questions ask you to describe a process you use to complete a task. Like technical questions, operational questions should be answered briefly and directly. The interviewer will ask you a follow-up question if they need additional information.

Example Answer

"Before I sign off on a completed job, I go through a series of steps to ensure that the job was done per the specifications, in compliance with code, and was completed properly. I review the specifications and blueprints to ensure the wiring, switches, and other components were properly installed. I also test the circuits to ensure there are no shorts or other malfunctions. Finally, I test the breakers to make sure they function properly. Only then do I sign off on the job."

4. What experience do you have with programmable computer logic (PCL) installation and repair?

This is another operational question that asks about your experience with a specific piece of electrical equipment. If you have experience with this, you can describe it. If you don't, you should be honest and state this, but then describe how you would go about acquiring the training and knowledge you need to work with this piece of equipment.

Example Answer

"Although I've worked with programmable computer logic devices, my experience with these is limited. I have enough knowledge to identify where the hardware should be located, how to configure and populate the chassis, and how the chassis should be wired. What I am not familiar with is the programming of the hardware and what steps need to be taken if there is a failure or fault. However, I am a quick learner, and I am confident I can acquire the knowledge needed to support one of these devices."

5. What are PCL's common defects?

This is a follow-up to the previous question. During an interview, you can anticipate follow-up questions any time you provide an answer. These indicate that the interviewer needs additional information about the topic or has a particular interest in this area and wants to explore it further. Follow-up questions are answered the same way standard questions are, directly and concisely.

Example Answer

"There are five common defects that can occur with PCL's. The most common one is the failure of the input/output system. Other issues include electrical noise interference, corrupted memory, problems with the power, or communications issues. All of these are easily diagnosed using the appropriate test equipment and can be fixed by replacing the affected component or module of the PLC."

6. Are you able to bend both EMT and RMC conduit following blueprints?

This question is a hybrid between a technical and an operational question. You need to know what the acronyms EMT and RMC refer to as well as how to bend these types of conduit. The best way to answer this type of question is first to define the different types of conduit, and then describe how you would go about bending them.

Example Answer

"Rigid metal conduit, known as RMC, and the electrical metallic tubing, or EMT, have similar qualities except that EMT has an external plastic coating. Both of these are bent in a similar manner using a conduit bending tool. The difference is, when bending EMT, I usually place a piece of protective tape on the tool so as not to scratch the coating and expose the metal. This is important since the EMT is typically used for installations where the conduit is exposed in an indoor setting."

7. What is your method for calculating wire fill?

This is another hybrid technical and operational question. You have to understand wire fill and what it means. Then you need to describe how you go about calculating wire fill and choosing the right components. Doing both of these will demonstrate your qualifications for an electrician's job.

Example Answer

"You need to be able to calculate wire fill to determine the correct size junction and outlet boxes needed for a wiring job. The first step is to determine the number and size of each conductor. Once you know this, you can determine the volume of the conductors. This determines the size of the outlet or junction box that you need to use to wire the circuit per code safely. There are several online tools and phone apps you can use to make this job simpler and more accurate."

8. How would you determine the number of amps you can put on a 500 mcm conductor?

You probably already recognize this as another hybrid technical and operational question. Your answer should include both the definition of the wiring and a statement about the number of amps it is capable of conducting. Keep your answer brief and direct, and anticipate follow-up questions.

Example Answer

"Thhn wire is primarily used in conduit for services, feeders, and branch circuits in commercial or industrial applications. It contains 37 strands and is slightly less than an inch in diameter. Its maximum capacity is 430 amps at high temperature."

9. How do you prevent high-voltage electrical systems from breaking down?

This is a general operational question. It does not refer to a specific task or technical aspect of an electrician's job. This asks what general processes and procedures you use to maintain electrical systems. Even though the question is general in nature, your answer should be specific and concise. You can anticipate that the interviewer will ask a follow-up question based on the information you provided in your answer.

Example Answer

"Maintaining high-voltage electrical systems and keeping them operational requires regular maintenance, frequent inspections, and safe operational procedures. You need to ensure that the circuits are not overloaded and that anything plugged into the system has the right voltage and amperage ratings. You also need to inspect the system to make sure that the components are not wearing out and that there are no frayed wires or other damaged components on the system."