7EA Users Group – Page 2 – Combined Cycle Journal

Damage report on a Mark I SCR static-exciter failure

7EA Users Group, Controls, Frame 6 / By Team-CCJ

LEGACY CONTROLS FORUM, NO. 6 IN A SERIES By Luke Williams, PE, consultant www.geLegacyGasTurbineSupport.com An MS7001B gas turbine with Mark I Speedtronic™ controls and SCR static exciter-regulator experienced overcurrent damage to its exciter on a normal startup. Operators think the overexcitation event lasted for several minutes. However, an overexcitation alarm was not received and the […]

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Protecting MK4, MK5 & EX2000 turbine controls from costly failures

7EA Users Group, 7F Users Group, Frame 6 / By Team-CCJ

If you’re managing MK4, MK5, or EX2000 platforms, this Technical Information Post (TIP) from AP4 Group demands your attention (Download here). These “classic” control systems rely on EEPROMs—and in the case of MK5 and EX2000, the U9 chip—to store essential software and configuration data. Failures of these components, increasingly common in systems over 25 years

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ACCUG: Global collaboration drives air-cooled condenser innovation

501 F&G Users Group, 7EA Users Group, 7F Users Group, Advanced GTs, CCUG / By Team-CCJ

The 15th annual meeting of the Air-Cooled Condensers Users Group (ACCUG) was held at the University of East London (UK) July 23-25, 2024. Principal content categories were chemistry and corrosion, air-cooled condenser (ACC) design and performance, and system operation and maintenance. The event was chaired by Andy Howell, EPRI; Barry Dooley, Structural Integrity (UK); and

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LTUG25: Advancing Frame 5, 6B and 7E together

7EA Users Group, Frame 6 / By Team-CCJ

The Legacy Turbine Users Group (LTUG), part of the Power Users suite of end-user networks, returns this June with its highly anticipated 2025 conference, gathering Frame 7EA, Frame 6B, and Frame 5 owner/operators, OEMs, and independent service providers for four days of collaborative learning, solution sharing, and fleet updates. Held at the Hilton Minneapolis, June

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Legacy Gas Turbines: Main story lines at LTUG24 reveal how to recover after taking a punch

7EA Users Group, Frame 6 / By Team-CCJ

To some, here’s the distinction between reliability and resiliency: Reliability is avoiding a punch; Resiliency is recovering as quickly as possible from a punch. Aging assets, such as those with older turbine models, are likely going to take more punches than they avoid because the resources to avoid the punch are devoted to newer, more

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Borescope inspections often more important than ever

7EA Users Group, 7F Users Group, Frame 6 / By Team-CCJ

With all the sophisticated gas-turbine inspection technologies available today—including ultrasonic, eddy current array, and phased-array ultrasonic—one might think the borescope had lost a step in status. Nothing could be further from the truth. Borescope capabilities have improved dramatically over time and they put your eyes right into the guts of critical plant equipment—to warn of

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Updating calculations of maintenance intervals, factored hours

7EA Users Group, Frame 6 / By Team-CCJ

Legacy Turbine Doctor, No. 4 in a series By Luke Williams, PE, Consultant www.geLegacyGasTurbineSupport.com The first article in Luke Williams’ continuing column, Legacy Turbine Doctor, published last summer (Are your GE B/E-Class hot parts and rotor really near ‘end of life?’), posited that gas-turbine operation at loads less than base would extend the OEM-recommended service

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Controls: Excess-fuel trip logic mitigates explosion potential

7EA Users Group, 7F Users Group, Controls, Frame 6 / By Team-CCJ

Legacy Turbine Doctor, No. 3 in a series By Luke Williams, PE, Consultant www.geLegacyGasTurbineSupport.com An MS6001B in Florida experienced a significant failure in 1994 when its stop-ratio valve (SRV) servo failed. On startup, the unit cranked and fired successfully; however, the valve continued to open. The failure was caused by the servo sticking at a

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How to upgrade, replace under-performing circuit breakers

7EA Users Group / By Team-CCJ

HIGH-VOLTAGE ELECTRICAL EQUIPMENT GE’s 7EA gas turbine is widely respected for its reliability, operational flexibility, and efficiency in simple-cycle, combined-cycle, and cogeneration systems, and mechanical-drive applications (Fig 1). This frame has been upgraded and improved continuously since its introduction some three decades ago. Today, it is rated up to 90 MW in simple-cycle service. Combined

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GAS TURBINES: ASME accords Kansas combined cycle Historic Landmark status

7EA Users Group / By Team-CCJ

The city of Ottawa’s gas-turbine-powered combined cycle was honored as an Historic Mechanical Engineering Landmark by the American Society of Mechanical Engineers, Sept 13, 2024, in a special ceremony conducted in the Ottawa Memorial Auditorium. Dave Hunsaker, electric superintendent for the city, accepted the award from ASME Fellow Jared Oehring, a member of the society’s

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