AP4 Group – Full-Service Heavy-Duty & Aeroderivative Industrial Gas Turbine Maintenance Provider.

Field Service Solutions

AP4 Group's Field Service Divisions Consist of:

AP4 Power Services – provides mechanical and controls field engineering services for aeroderivative turbines. Whether you’re in need of an engine borescope, an engine removal & re-installation, or DLE Mapping AP4 Power Services can help.

Turbine Controls & Excitation Group (TC&E) – Is your go-to provider of all large frame gas and steam turbine controls field services.  From basic controls, exciter, or LCI maintenance and troubleshooting, so implementing full turbine controls upgrades… checkout our website for the extensive list of offerings.

Maine Automation
Maine Automation is an electrical process control instrumentation construction and commissioning contractor that specializes in the power generation industry. Rooted in the power generation section but also serving other industrial, municipal, and commercial customers alike, Maine Automation has the experience and talent you’re looking for to support your next project.

High-level Overview of our Field Service Offerings:

Aeroderivative Turbines

  • Mechanical Field Services
  • Controls Field Services
  • DLE Mapping
  • O&M Contracts


  • Turbine Controls: MKV, MKVI, MKVIe, Emerson™ Ovation
  • Excitation: EX2000, EX2100, EX2100e
  • LCI: Innovation Series, LS2000, LS2100, LS2100, TMEIC™ LCI DFEs
  • NERC MOD Testing
  • Training

Maine Automation

  • High, Med, Low voltage wiring
  • Motor Control Centers
  • Instrumentation Calibrations & Loop Tuning
  • VFD Start-up & Troubleshooting
  • Automatic control valve & cylinder repair & Reconditioning
  • Maintenance shutdowns, plant outages, special projects, seasonal support

Contact us 24/7/365 for any emergency needs or project support.  If it takes electricity to make electricity, we can work on it.

Full-Service Maintenance & Upgrades

Our team responds to your on-site maintenance & upgrade needs with our experienced team of controls and mechanical engineers.

Our Solutions

AP4 Power Services specializes in controls, excitation, and LCI systems on GE™ heavy-duty gas and steam turbines. These services include a wide variety of controls maintenance, troubleshooting, and system upgrades. Our OEM-trained field engineers are here to ensure your equipment operations are reliable and efficient.

Power plant personnel look to AP4 Power Services when they are seeking a trusted non-OEM service provider that can help develop and implement customized control system projects. We are a trusted installation partner for many non-OEM equipment vendors throughout the industry.

From basic troubleshooting to DLE Mapping and mechanical service and maintenance, AP4 Power Services can meet all of your aeroderivative needs. Our expert team of Controls & Mechanical Field Engineers are ready and able to provide the on-site support you require.

Industry Benefits


Using the latest technology, components, and lessons learned through decades of experience, AP4 Power Services can ensure complete reliability for both start-up and continuous operation.


This is the key to success in today’s competitive power markets. Heat Rate, Capacity, Start-Up, and Maintenance Costs are critical to the success of aging power plants.


Spending good money where it makes the most difference! We understand that O&M budgets are shrinking, so we work with the plants to understand where and when to repair, replace, or upgrade for maximum return.


Aging systems can continue to provide reliable service for many years to come with the proper service, maintenance, and repairs. Push your upgrades out 5-10 years with confidence.