BESS Electrical Design Engineer Lead

Larsen & Toubro; Bengaluru; On-site; INR 1,200,000 - 2,000,000; Full time

Job summary

Larsen & Toubro in Bengaluru seeks an experienced BESS Electrical Design Engineer to lead design, analysis, and validation of electrical systems for utility-scale battery energy storage solutions, including HV/LV architecture, protection schemes, and grid interconnection.

You will develop complete wiring diagrams, SLDs, and interconnection details, define cable sizing and busbar design, coordinate with BMS/EMS, and support UL/IEC certification and FAT/SAT testing.

Qualifications

• Bachelor’s or Master’s in Electrical Engineering, Power Engineering, or related fields.
• 5–10 years in electrical design for BESS, Solar Inverters, UPS, EV charging, or power systems.
• Experience with lithium-ion safety, HV DC systems, and grid interconnection is strongly preferred.

Responsibilities

• Develop complete electrical architecture for BESS including HV/LV racks and string design, DC bus architecture, PCS/inverter integration, LV auxiliaries.
• Prepare SLDs, wiring schematics, and interconnection drawings.
• Define cable sizing, protection device selection, busbar design, and interconnection details.
• Prepare technical docs such as SLDs, wiring diagrams, protection studies, BoM, installation manuals.
• Support UL/IEC certification activities with required electrical artefacts.
• Design HV DC circuits including contactors, fuses/breakers, DC isolators.
• Define creepage/clearance, dielectric strength, and insulation coordination.
• Ensure compliance with IEEE, IEC, NEC, CEA, NFPA, UL, and utility grid codes.
• Develop electrical protection strategies and coordinate with BMS/EMS.
• Support arc-flash studies, fault current calculations, and grounding design.
• Integrate battery racks, PCS, MV skids, transformers, HVAC, and control systems.
• Prepare FAT/SAT test procedures and assist in prototype builds and field commissioning.
• Collaborate with Battery engineering, Power electronics/PCS, Thermal/HVAC teams, and Supply Chain.

Skills

DC and AC power

Cable sizing and protection

Grounding/earthing

Power system integration

Education

Bachelor’s or Master’s in Electrical Engineering

Tools

AutoCAD Electrical

EPLAN

SolidWorks Electrical

ETAP

DigSilent

Job description

Role Summary

The BESS Electrical Design Engineer is responsible for the design, analysis, and validation of electrical systems for utility-scale and industrial battery energy storage solutions. The role includes designing HV/LV electrical architecture, protection schemes, cable routing, battery rack wiring, earthing/grounding, and grid interconnection while ensuring compliance with global standards and safe, reliable operation.

Key Responsibilities

• Develop complete electrical architecture for containerized or modular BESS that includes HV battery racks and string design, DC bus architecture, PCS/inverter integration, LV auxiliaries (HVAC, fire systems, controls, lighting)
• Prepare SLDs (Single Line Diagrams), wiring schematics, and interconnection drawings.
• Define cable sizing, protection device selection, busbar design, and interconnection details.
• Prepare technical documentation such as SLD, Wiring diagrams, Protection coordination studies, Electrical BoM (Bill of Materials), Installation manuals
• Support UL/IEC certification activities with required electrical design artefacts.
• Design HV DC circuits including Contactor, Fuses/breakers, DC isolators,
• Define creepage/clearance, dielectric strength, and insulation coordination.
• Design LV AC/DC circuits for auxiliary systems and control circuits.
• Ensure compliance with IEEE, IEC, NEC, CEA, NFPA, UL, and utility grid codes.
• Develop electrical protection strategies: overcurrent, short circuit, earth fault, arc flash, isolation monitoring.
• Work with BMS and EMS teams to align electrical protection with software/logic protection.
• Support arc-flash studies, fault current calculations, and grounding/earthing design.
• Ensure compliance with UL 9540, UL 1973, IEC 62933, and NFPA 855.
• Integrate battery racks, PCS/inverters, MV skids, transformers, HVAC, fire suppression, and control systems
• Develop cable routing, harnessing plans, and connector specifications.
• Work with mechanical teams on enclosure layout, HVAC panel integration, and mounting systems.
• Define interface control documents (ICD) for OEM components.
• Prepare FAT/SAT test procedures for electrical systems.
• Support prototype builds, subsystem testing, and field commissioning.
• Validate system performance through electrical measurements and simulations.
• Collaborate with Battery engineering, Power electronics/PCS engineering. Thermal/HVAC teams, Fire safety teams, Mechanical engineering, Firmware & controls, Supply Chain
• Provide technical support to sales, application engineering, and project delivery teams.

Required Qualifications

Bachelor’s or Master’s in Electrical Engineering, Power Engineering, or related fields.

Technical Skills

• Strong knowledge of DC and AC power systems (up to 1500 VDC, 400–800 VAC, MV if applicable).
• Experience with cable sizing, protection coordination, and grounding.
• Proficiency with design tools such as AutoCAD Electrical, EPlan, or SolidWorks Electrical.
• Knowledge of ETAP/DigSilent for fault and protection studies (advantage).
• Understanding of PCS, BMS, EMS, and thermal system interaction.
• Familiarity with global standards (UL, IEC, IEEE, NFPA).

Experience

• 5–10 years in electrical design for BESS, Solar Inverters, UPS, EV Charging, or power systems.
• Experience with lithium-ion safety, HV DC systems, and grid interconnection is strongly preferred.
• Experience supporting FAT/SAT and field commissioning is an advantage.