Gas Turbine Controls Corporation (GTC) and its subsidiaries, GTC Services (USA) and GTC Services Ltd. (UK), present this document prepared for an informed and experienced Power Generation audience familiar with the GE Speedtronic Mark V, affectionately called mk5.

Our customers requested a straightforward summary “White Paper” citing verifiable examples and facts against a traditional commercial brochure. Here is the result; we hope you find it insightful, easy to read and a true representation of GTC’s customer centric philosophy.

We organised this document with succinct and numbered issue descriptions and attachments, of which the latter carry the most informative parts of the update.

Common Concerns

These are the most frequent issues raised by end users about the mk5 and GTC’s response and support options.

  1. Obsolescence of Parts? Not Quite…

Background: A few years ago, the Original Equipment Manufacturer (OEM) released a Mark IV Life-Cycle Support Notice indicating obsolescence and End-of-Production (EOP) of some parts.

For the mk5, the OEM has already published a mk5 End-of-Life letter but at the time of writing this update, we are not aware of an equivalent obsolescence or EOP Life-Cycle Support Notice for it.

In any case, as described below, we will demonstrate GTC’s ability to support the mk5 in all aspects, including:

·         Parts

·         Repairs

·         Training

·         Field Service

·         Operator Interface

·         Panel Renewal

·         Remote Support

·         Etc.


  1. EEPROM Backup

We cannot overemphasise the importance of having EEPROM backups.

The OEM may or (most likely) may not carry the right backups and the “Requisition Library” was discontinued decades ago.

As such, should your EEPROMS get damaged or corrupted, without a backup or an identical sister unit, the only fix may be “a complete panel upgrade”! Seriously.

  1. Operator Interface

GTC provides replacement-in-kind (RIK) for the mk5 original operator interface áIñ, also called I-dos, and the áHMIñ.

The RIK is a low cost, reliable solution to renew the hardware after decades—literally—of satisfactory service and GTC also offers a revamped option with solid state drive (NANDFLASH card).

  1. Spare Parts Availability

GTC carries an unparalleled inventory of Cards, Terminal Boards and Power Supplies and our Service Center is a state-of-the-art facility, where visitors are always welcome.

GTC’s repair technology ensures the availability of parts: considering our inventory and repair technology compared to the current consumption rate, we estimate an adequate in-house supply of mk5 parts for 10~15 years, without considering the mk5 panels that will become available due to turbine upgrades or decommissions.

For Cables and Ribbon Cables, see Item 8.

With the Sales and Repair data of mk5 components, collected since 2001, GTC prepared a Pareto (80/20 rule) analysis to determine the components that you should have in stock to mitigate the risk of extended forced outages.

  1. Technical Support and Training

Besides the inventory of parts and repairs at the Service Center, GTC can support the continued operation of your mk5 with field service, including remote support (troubleshooting) and training.

The mk5 Health Check can help detect and resolve chronic and nuisance problems in the panel. Our field service, health check and training classes consistently receive high praise from customers and participants.

  1. Longevity™

This is a customizable service created by GTC to alleviate the concerns regarding the availability of support and parts. Longevity™ provides an “evergreen warranty” for the duration of the agreement for parts and repairs.

GTC has signed multi-year Longevity™ program agreements with world-class oil and gas companies.

  1. SD-card Printer Replacement

GTC is developing an SD-card solution to eliminate the mk5 printer and all the hassle that comes with it… expect to see it by 2018.  : paper, ink-ribbon, never works when it’s needed – ETA 2018Q2

  1. Cable Kit for the mk5

GTC offers a kit with replacement cables for the mk5 panel.

After 10+ years in operation, you should consider the renewal of the panel cables, as they may become brittle and cause communication failures, ground faults and alarms.

After 15+ years, you will most likely find that the cable renewal option has upgraded itself from a consideration to a necessity. The GTC mk5 cable kit mitigates the faults due to aging panel cables.

Regarding aging field wiring, we also recommend the renewal of field wiring and JB’s terminal boards, especially in high temperature locations like the exhaust area.

  • GTC supports mk5 panel cabling with parts and an expert technician to remove and install the new cabling, a 4-day
  • GTC supports field wiring and JB terminal box renewal installation, loop checks and recommissioning, a 4-week process.


Should you have any questions or concerns regarding GTC’s ability to support your mk5 panel, our staff of Parts Specialists, Service Center, Engineering and Field Service is always available—simply contact us at

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Your safety, as well as the health and welfare of our employees, associates, clients and partners around the world is our priority.

We urge everyone to follow Government Guidelines and maintain strict social distancing.