15 Charging Infrastructure Interview Questions for EV Roles

OCPP, CCS, IEC 61851, AIS-138, payment + roaming, grid-integration + site-planning — the 15 questions asked by Tata Power, Statiq, ChargeZone, ABB E-mobility.

Charging-infrastructure interviews probe standards-fluency, grid-integration knowledge, payment + roaming architecture + the hardware-software interface that makes a charging session work. Here are 15 questions that recur and the answers that signal real production exposure.

Standards + protocols

Walk through the CCS DC fast-charging handshake from plug-in to current flow.
What's the difference between OCPP 1.6 and OCPP 2.0.1? Why does the upgrade matter?
Explain IEC 61851 vs IS 17017 (the Indian variant). What does AIS-138 add on top?
Walk through OCPI roaming architecture between two CPOs.
What's ISO 15118 (Plug & Charge) and what's its adoption status in India?

Hardware + power-electronics

Walk through a 60kW DC fast-charger block diagram. Cover AC input + PFC + DC output + isolation.
Why are SiC MOSFETs preferred over IGBTs for 350kW chargers?
What's the difference between liquid-cooled vs air-cooled DCFC cables?

Site planning + grid integration

Walk through site selection for a new 6-stall DC fast-charging hub. Cover load + footprint + permits + dwell-time logic.
What grid-tie size do you need for a 6-stall 150kW DCFC hub? Show the math.
How do you handle utility transformer constraints with battery buffering?
Walk through the smart-charging algorithm you'd implement for a 50-stall workplace charging deployment.

Payment + driver experience

Walk through your payment-flow design for a multi-CPO roaming user.
What's the unit-economics impact of charging-session abandonment rates?
How do you architect anti-fraud for charging-network payment systems?
Walk through the driver-app feature set you'd ship for a new Indian charging network.

Where to go from here

Charging-infrastructure interviews reward standards-vocabulary fluency + lived deployment experience. Read the OCPP 2.0.1 spec, the IEC 61851 + AIS-138 standards, and one CCS / CHAdeMO handshake primer. Pair with deployment-side knowledge (DISCOM tariffs, BIS / BEE permits, real site-planning trade-offs) and you'll beat the candidates who only know the spec from textbooks.

Make this real: create a free emobility.careers account to match with EV jobs, see live salary medians and unlock 200+ JD templates. Want hands-on training? Check out the AICTE-approved EV programs at DIYguru — the largest EV academy in India with placement support across OEMs, charging operators and Tier-1 suppliers.