ABB embedded interview prep

Roles they hire for

• Drives and motor control firmware engineer
• Robotics software engineer

What they emphasise

• Variable-speed drives
• Robotics
• IEC 61508 safety functions

Brush up on

Motor controlSafe torque offEtherCATIEC 61508Encoders

How the rounds usually run

A typical regulated product loop for embedded roles. Companies vary by team and seniority.

Recruiter or hiring-manager screen

• Background in regulated or safety-critical work
• Role fit

Example: Have you worked under a formal development process? Which one?

Technical 1: C, RTOS and state machines

• Embedded C and RTOS fundamentals
• State machine design and implementation

Example: Implement a table-driven state machine in C and explain how you'd test every transition.

Technical 2: Safety and design

• Fault detection, safe states and recovery
• Risk analysis and software FMEA
• Verification and traceability

Example: How would you detect a stuck sensor reading?

Panel: cross-functional

• Working with systems, hardware and quality engineers
• Handling changes under change control

Example: A hardware change lands late. How do you assess its impact on certified firmware?

HR

• Motivation and values
• Logistics

Example: Why do you want to work on medical or industrial devices?

Practice questions

Original questions written for ABB's focus areas, not leaked ones.

1. Explain safe torque off and how firmware and hardware share the job.
2. How does EtherCAT achieve tight synchronisation across many devices?
3. Design encoder handling that detects a broken cable.
4. How do you tune a speed loop without risking the machine?
5. What happens in a drive when the DC link voltage rises during braking?

Your prep playlist

Design rounds to practise

Themes are inferred from ABB's public product lines.