The work we provide through our Technical Services Division is key to what makes O’Connell Electric a full service electrical contractor. We provide testing, commissioning, and preventative maintenance services critical to safe, reliable electrical systems operation—for businesses, at substations, and on power lines—as well as electrical engineering design and support services.

Additionally, as a Doble Engineering client, O’Connell has access to the industry’s most sophisticated diagnostic test equipment as well as 25 million test results on over 100,000 types of apparatus. As a member of TEGG, our technicians and management teams are guaranteed to be current with the latest training, procedures, and equipment, allowing us to maintain the highest level of electrical systems reliability, performance, and maintenance.

The projects we work on are as diverse as the services we offer. For Steel Winds wind farm, what began as a small condition assessment project on a retired substation grew to full electrical construction at the site. O’Connell’s diagnostic results along with substation design modification recommendations convinced developers we were right for the job. On a large power generation decommissioning project, O’Connell was contracted to perform testing and commissioning at eleven active substations while maintaining power. We also performed acceptance testing across 53 circuit miles of underground 115KV cable for the project.

With O’Connell, you’ll never be left in the dark. Our 24-hour emergency response team is at the ready 7 days a week.


Site Evaluation & Custom Programs

Electrical Equipment Condition Assessment

Unification Programs for Companies with Multiple Facility Locations

Arc Flash Analysis Utilizing SKM Power Systems Software

Facility Mitigation Recommendations

NFPA 70E Compliance

  • Field Data Collection Procedures
  • Energized Work Procedure Creation

Design/Build & CAD Services

Short Circuit Coordination Studies

Power Coordination Studies

Protective Relay Settings Review

Protective Relay Upgrades

Power Quality Studies & Troubleshooting

Electrical Efficiency & Load Studies

Substation Modification & Upgrade Recommendations

Power Factor Correction

Systems Commissioning

Soil Resistivity Testing & Ground Grid Design

Surge Suppression Design & Replacement

Non Destructive Cable Testing

Time Domain Reflectometer Service (TDR)

Very Low Frequency Testing (VLF)

Cable Polarization Index Calculations

High Potential Testing

  • Up To 550,000 Volts

Magnetic Impulse Fault Detection

  • Up To 3700 Joules

Underground Cable Locating

  • Onsite Emergency Fault Repairs

Acoustical Fault Detection

Partial Discharge & Ultrasonic Testing

Splicing & Terminations

Thermographic Testing of Splices & Terminations

Medium & High Voltage Cable:

  • Inspection & Commissioning
  • Doble Insulation Power Factor Testing (M4000)

Doble Insulation Power Factor Testing (M4000)

  • Call 800.343.2176

Custom Maintenance Programs

TEGG Service Provider

Equipment Life Extension Programs

Ultrasonic & Thermographic (Infrared) Inspections

Megger Testing

Power Quality Analysis

De-energized Equipment Maintenance

Energized Equipment Maintenance

Voltage Regulator Service & Testing

Soil Resistivity Testing & Ground Grid Design

Surge Suppression Design & Installation

Non Destructive Cable Testing

System Load Studies

Harmonic Distortion Analysis

Oil Sampling & Lab Analysis (DGA)

  • Oil Sampling & Lab Analysis (DGA)


  • Assembly
  • Commissioning
  • Internal Inspections
  • Field Repairs
  • Turns Ratio Testing
  • Winding Resistance Testing
  • Load Tap Changer Service & Testing


  • Dielectric Power Factor
  • Sweep Frequency Response Analysis

Maintenance & Testing of

  • Oil-filled Circuit Breakers
  • Vacuum Circuit Breakers
  • Battery Systems
  • Network Protectors
  • Gas, Steam & Hydro Turbines
  • Surge Suppression

SF6 (Sulfur Hexafluoride)

  • Circuit Breaker Maintenance & Testing
  • Gas Reclamation & Leak Detection

Circuit Breakers

  • Repair
  • Timing & Travel-motion Analysis
  • Primary Injection Testing
  • Secondary Injection Testing
  • Voltage & Current Ratings
  • Microprocessor Controlled Trip-unit Retrofits
  • Mobile Test Equipment for Onsite Work

Protective Relays

  • Testing & Calibration
  • Replacement & Refrofits

24/7/365 Emergency Response

  • Call 800.343.2176

Testing & Commissioning Activities Supervised by Onsite Field Engineers

Turnkey Systems Commissioning

Substation Acceptance Testing & Commissioning

Substation Equipment Condition Assessment

Transformer Assembly, Internal Inspections & Commissioning

Dielectric Fluid Sampling & Lab Analysis

Complete Protection Circuit Verification & Functional Testing

Current & Potential Transformer Acceptance Testing & Commisioning

SF6 (Sulfur Hexafluoride) Circuit Breaker Filling & Testing

Dew Point & Moisture Content Analysis

Vacuum Bottle Testing

Doble Sweep Frequency Response Analysis

Protective Relay Programming & Acceptance Testing

  • All Manufacturers

Commissioning Protection Scheme Verification & Drawing Reviews

  • Red/Green/Yellow Mark-ups

Soil Resistivity Testing

Ground Grid Inspection & Testing

Electrode Inspection & Testing

Surge Suppression Inspection & Testing

Medium & High Voltage Cable

  • Doble Insulation Power Factor Testing (M4000)
  • Inspection & Acceptance Testing
  • Splice & Termination Testing

Low Voltage Cable Acceptance Testing

Thermographic & Ultrasonic Inspections

Functional Testing of All Circuit Breakers Including Primary & Secondary Injection Testing

Battery Systems Acceptance Testing & Commissioning

Network Protector Acceptance Testing & Commissioning

Systems Troubleshooting & Debugging

Relay Calibration, Testing, Repair, Retrofits, & Upgrades

  • All Manufacturers

Turnkey Solutions: Design to Programing to Full Functional Testing

System Start-up, Support & Debugging

Doble F6150 3-Phase Power Simulator Relay Testing

End-to-End GPS Satellite Testing

Acceptance Testing for Point of Interconnect (POI)

  • Utility Witness Testing

Current & Potential Transformer Testing

Protection Scheme Varification

Sequential Event Recording & Post Fault Analysis

24/7/365 Emergency Response

  • Call 800.343.2176