Interview questions

Electrical Engineer Interview Questions

19 electrical engineering interview questions on power factor, three-phase, grounding, PCB design and troubleshooting, with what a strong answer contains.

Updated October 27, 2026

What's here

19 Electrical Engineer interview questions, grouped into 4 areas: fundamentals, design and standards, troubleshooting and testing and projects and behavioural questions. Each one comes with why it is worth asking and what a strong answer contains, so the same question can be scored the same way by different interviewers.

Tailor at least one section to the candidate's specialism: power, electronics, controls or utilities
Ask them to sketch a circuit or single-line diagram and explain it; it exposes depth fast
Include a troubleshooting scenario and judge method over the final answer

Try it free →Read the full article ↓

Cohesyve finds, contacts and tests Electrical Engineer candidates on the real work, then ranks them for these interviews. Ten candidates free, no card.

Preparing for this interview yourself? Practise it free →

Electrical engineers design, test and maintain electrical systems, from circuit boards and control panels to building power distribution and utility networks. The specialisms differ a lot, so a good interview mixes fundamentals every electrical engineer should know with questions on the candidate's own area, plus troubleshooting and project behaviour. These questions are useful for hiring managers building a technical interview and for engineers preparing for one.

Fundamentals

Core concepts every electrical engineer should be able to explain clearly.

1
Explain power factor. Why does it matter, and how can it be corrected?
Why ask it
A fundamental concept with practical cost implications.
What to look for
Ratio of real power to apparent power, caused by phase difference between voltage and current (inductive or capacitive loads), leading to higher currents and losses. Correction with capacitor banks or synchronous condensers.
2
What are the advantages of three-phase power over single-phase?
Why ask it
Basic power systems knowledge.
What to look for
More constant power delivery, more efficient transmission for the same conductor material, simpler motor starting, and smaller conductors for the same power.
3
Explain the difference between grounding and bonding.
Why ask it
Critical for safety and frequently confused.
What to look for
Grounding connects the system to earth; bonding connects metal parts together so they are at the same potential and fault current has a low-impedance path to trip protection.
4
How does a transformer work, and what causes losses in it?
Why ask it
Tests understanding of electromagnetic principles.
What to look for
Mutual induction between windings, turns ratio sets voltage ratio. Losses: copper (I squared R), core losses (hysteresis and eddy currents), and stray losses.
5
What is the purpose of a decoupling capacitor on a circuit board?
Why ask it
Common electronics question that shows practical design knowledge.
What to look for
Supplies local current during fast switching and filters noise on the power rail. Placement close to the IC pins matters.

Cohesyve

Before the Electrical Engineer interviews, see who can do the work

Cohesyve finds and contacts Electrical Engineer candidates from your job description and tests each one on an AI job simulation of the role, so these questions go to a ranked shortlist. Ten candidates free, no card.

Try it free →Book a 30-min demo

Design and Standards

How the candidate applies fundamentals to real designs.

6
Walk me through how you size a cable or conductor for a circuit.
Why ask it
A practical, everyday design task in power roles.
What to look for
Load current, installation method and derating for temperature and grouping, voltage drop limits, short-circuit withstand, and checking against the applicable code such as the NEC or local equivalent.
7
How do you approach protection coordination in a distribution system?
Why ask it
Tests understanding of selective protection.
What to look for
Making sure the device closest to a fault trips first, using time-current curves, coordination studies and software tools, and balancing selectivity with arc flash and equipment protection.
8
Describe a PCB or control panel you designed. What trade-offs did you make?
Why ask it
Real design experience in the candidate's own area.
What to look for
Specific requirements, component choices, layout considerations (signal integrity, thermal, EMC), testing approach and lessons learned.
9
Which design and simulation tools do you use?
Why ask it
Tool fit affects ramp-up.
What to look for
Named tools relevant to their field (such as AutoCAD Electrical, ETAP, SKM, Altium, KiCad, SPICE or MATLAB) with examples of what they did in them.
10
How do you design for safety and compliance?
Why ask it
Electrical work carries safety risk and regulatory requirements.
What to look for
Applying relevant codes and standards, hazard and arc flash considerations, design reviews, documentation, and testing before energising.

Troubleshooting and Testing

How the candidate finds and fixes faults methodically.

11
A motor keeps tripping its overload. How would you diagnose the problem?
Why ask it
Classic troubleshooting scenario.
What to look for
Check the load and mechanical condition, measure current on all phases, check for phase imbalance or loss, verify overload settings, inspect insulation resistance, and check supply voltage.
12
Which test equipment do you use most, and how do you work safely when testing live equipment?
Why ask it
Safety and practical skill.
What to look for
Multimeters, clamp meters, insulation testers, oscilloscopes and power analysers. Safety: de-energise where possible, lockout/tagout, proper PPE, test-before-touch, and following the employer's electrical safety rules.
13
Tell me about the hardest electrical fault you have tracked down.
Why ask it
Shows depth and persistence.
What to look for
Structured approach, hypotheses tested one at a time, data gathered, root cause found and a fix that prevented recurrence.
14
How do you validate a new design before it goes into production or is energised?
Why ask it
Tests quality discipline.
What to look for
Design reviews, simulation, prototype testing, commissioning checklists, staged energisation, and documented test results.

Projects and Behavioural Questions

How the candidate works with others and manages engineering projects.

15
Describe a project where requirements changed late. How did you handle it?
Why ask it
Engineering projects rarely stay fixed.
What to look for
Assessing impact on design, cost and schedule, communicating trade-offs, updating drawings and documentation, and getting sign-off before changing.
16
How do you explain a technical recommendation to a non-engineer, such as a client or project manager?
Why ask it
Engineers must communicate with non-technical stakeholders.
What to look for
Plain language, focus on impact (cost, safety, schedule), visuals where helpful, and a clear recommendation.
17
Tell me about a design mistake you made. What did you learn?
Why ask it
Honesty and learning culture.
What to look for
Ownership, how it was caught, impact, correction and the process change that followed.
18
How do you keep your technical knowledge current?
Why ask it
Standards and technology change.
What to look for
Code updates, professional bodies such as IEEE or IET, courses, and progress toward or maintenance of a professional engineering licence where relevant.
19
How do you work with electricians, technicians or manufacturing on site?
Why ask it
Designs succeed or fail in the field.
What to look for
Respect for practical experience, site visits, listening to feedback on buildability, and clear drawings and instructions.

Running the interview well

1Tailor at least one section to the candidate's specialism: power, electronics, controls or utilities
2Ask them to sketch a circuit or single-line diagram and explain it; it exposes depth fast
3Include a troubleshooting scenario and judge method over the final answer
4Check safety habits explicitly; they matter as much as technical knowledge
5Verify any professional licence claims if the role requires stamped drawings

Common questions

What technical questions are asked in an electrical engineering interview?

Common topics include Ohm's and Kirchhoff's laws, power factor, three-phase systems, transformers, motors, grounding and bonding, protection, circuit design and component choices. Expect deeper questions in your specialism, such as PCB design, power distribution or controls.

How should I prepare for an electrical engineer interview?

Review fundamentals, prepare two or three projects you can explain in detail including trade-offs, practise sketching diagrams, and prepare a troubleshooting story. Know the codes and tools used in the role you are applying for.

Is a PE licence required for electrical engineers?

Not for every role. In the US, only a licensed Professional Engineer can sign and seal engineering plans or offer engineering services to the public. Entry-level roles do not require one, and each state sets its own licensing rules and exemptions.

Cohesyve · Skill assessments for hiring

Save these questions for the Electrical Engineer candidates who can do the work

Cohesyve takes your Electrical Engineer job description, finds candidates, reaches out to them and runs an AI job simulation of the real work, then returns a ranked shortlist.

1,500+

assessments completed

50%

faster time-to-hire

5 min

from JD to assessment

Try it free →Book a 30-min demo

No credit card · 10 free candidates · Plans sized to your hiring volume

Case study: Indago Research went from 10–15 interviews per role to 3–4 →Plans from $199/month, sized to your hiring volume →

For candidates

Preparing for an Electrical Engineer interview yourself? Practise on an AI job simulation of the role. 3 free practice assessments, no card.

From the blog