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Field Service Technician III

NASS
St Louis, MO Full Time
POSTED ON 3/7/2026 CLOSED ON 4/5/2026

What are the responsibilities and job description for the Field Service Technician III position at NASS?

Overview

Field Service Technician III

North American Substation Services (NASS) is a national leader in transformer services and high‑voltage substation installation, maintenance, testing, and repair. With more than 20 years of experience, we deliver comprehensive, one‑stop solutions for utilities, industrial operations, and critical infrastructure across the United States. Our teams support the full lifecycle of substation and transformer assets, including installation, maintenance, major repairs, and diagnostic testing.

Core services include transformer assembly, oil processing, regasket and life‑extension work, substation apparatus testing, and high‑voltage equipment maintenance to ensure safe, reliable system performance. We work on a wide range of substation equipment—power transformers, breakers, switches, arresters, and control cabinets—and perform essential diagnostics such as TTR, winding resistance, insulation resistance, power‑factor testing, and oil analysis through our dedicated in‑house laboratory. With a nationwide fleet of mobile oil‑processing units, we provide rapid on‑site support backed by strong technical expertise , a commitment to safety, and disciplined field execution to keep critical power systems operating reliably and efficiently.

Benefits

  • Medical, dental, and vision coverage
  • 401(k) savings plan with company match
  • Health Savings Account (HSA) and/or Flexible Spending Account (FSA)
  • Life and AD&D insurance
  • Short-term and long-term disability coverage
  • Employee Assistance Program (EAP)


Perks

  • Competitive pay
  • Talent development through instructor-led and online learning
  • Career path planning
  • Incentives for professional certifications
  • Per diem for travel
  • Referral bonuses
  • Tuition reimbursement


Pay:

The hourly rate for this position is between $35 – $52 per hour.

Factors which may affect starting pay within this range may include geography/market, skills, education, experience, and other qualifications of the successful candidate.

Position Overview:

The Field Service Technician III serves as a senior field technician responsible for advanced assembly, maintenance, testing, diagnostics, and repair of transformers and high voltage apparatus. This role performs hands-on transformer services with minimal supervision and supports complex projects through technical expertise , troubleshooting, and leadership of junior technicians.

Responsibilities

  • Model and reinforce safe work practices, PPE requirements, and company safety policies.
  • Perform transformer testing and apparatus work as a lead technician on installation, maintenance, and emergency jobs.
  • Install, test, and maintain electrical apparatus with strong understanding of transformer components and field practices.
  • Troubleshoot and resolve issues identified during diagnostics and testing.
  • Interpret and analyze test results accurately, supporting field decisions.
  • Develop testing plans and assist with execution of field test procedures.
  • Operate oil processing and vacuum rigs, including dry-outs, circulation, and top-off procedures.
  • Complete documentation, inspections, job briefs, and work order entries.
  • Maintain professional communication with supervisors, crew members, and customers.
  • Install and assist with commissioning monitoring devices such as Calisto sensors


Qualifications

Required:

  • Five or more years of transformer services, substation apparatus work, or related high voltage field experience
  • High school diploma or GED
  • Valid driver’s license and insurable record
  • Ability to stand, walk, climb, and lift up to 50 lbs.
  • Ability to safely work in outdoor, energized, high voltage environments
  • Willing and able to travel frequently (:75%), including overnight and occasional international travel
  • Willingness to work overtime, nights, weekends, and holidays
  • Ability to complete background checks and medical evaluations


Preferred:

  • CDL or interest in obtaining one
  • NCCCO crane certification
  • Strong knowledge of mechanical and electrical maintenance tools
  • Familiarity with grounding, LOTO, and arc-flash boundaries
  • Ability to read diagrams, one-lines, schematics, and metering devices
  • Desire to develop additional transformer diagnostics and testing skills


Work Environment & Physical Requirements:

  • Outdoor field role with exposure to weather, noise, and energized equipment
  • Travel may include extended stays and international trips
  • Reasonable accommodations may be provided


EEO Statement

NASS, an Asplundh Power Company, is an Equal Opportunity Employer. All qualified applicants will receive consideration without regard to race, color, religion, sex (including pregnancy, gender identity, and sexual orientation), national origin, age, disability, veteran status, or any other protected characteristic. NASS does not engage with individual recruiters or third party staffing agencies. Unsolicited résumés will not be accepted.

#WEEMPOWERPOSSIBLE

Salary : $35 - $52

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