Technical skills Working knowledge of NEC (Article 625 in particular), NFPA 70E, and OSHA 29 CFR 1910 Subpart S. Proficient with multimeters, clamp meters, insulation-resistance testers, and torque tools; able to use an oscilloscope or data logger when a fault calls for it. What you'll do Diagnose and repair (Tier III escalation) Resolve the DC fast-charger faults that Tier I/II could not: power electronics, control and communication boards, contactors, cooling systems, cable and connector assemblies, and vehicle interoperability failures.