Generator Excitation Control Upgrades

The 200 Series is an excellent replacement for smaller brushless (with rotating diode wheel) or older DE exciters - both analog and digital.

The 400 Series Digital Excitation Control System (shown rack mounted above) is a microprocessor based controller that provides excitation control, flexible logic control and optional power plant system stabilization for synchronous machines in an integrated package. These most often incorporated in upgrades for SCT/PPT, potential source SCR bridges, Amplidyne, ALTERREX, GENERREX and the larger brushless and rotating DC exciters.

Contact TDS for further discussion, expected lead times, costs and  hardware availability to best meet your schedule needs.  

For Planned Outages

DECS - 400 shown in STG Cabinet

DECS - 250 shown in GTG Cabinet

If you are experiencing problems with any of the Generator excitation systems identified below, please contact us for your best engineered solution.

GE Amplidyne Voltage                                                               EMD Vickers

GE SCPT                                                                                      EM Rotating Exciters                          
GE Bus Fed                                                                                 Westinghouse

GE ALTERREX                                                                             Hitachi HIGEX
GE GENERREX                                                                            Siemens

GE Shunt SCR                                                                             GEC-Alstom 

GE PPT/Excitation Transformer Static Exciter Systems        ABB (Old BBC Static Exciters)
GE SCT/PPT Exciter System                                                     All OEMs Reg. with Shaft Driver DC Gen.
GE Digital EX2000 Exciter System                                            Basler Static Exciters
GE Digital EX2000 w/LCI Gas Turbine Static Start (7FA)

DECS - 250 Digital
Voltage Regulator

The Turbine Diagnostic Service, Inc. (TDS)generator specialist engineers are experienced in all types of excitation systems, from old shaft driven DC rotating generator exciters with amplidyne control, rotating exciters, alterrex, or static exciters.

TDS engineers are experienced in the static exciters from buss fed SCT-PPT exciters with analog regulators to the newer digital EX2000 regulator and excitation transformer or P bar winding.

TDS has the start-up experience to support your unit for the EX2000/LCI for the static start of the large gas turbine generators. 

TDS can provide upgrades for any type of excitation system. With specific hands-on experience, our engineers will design and install your upgrade using existing interconnecting cables connected to the new terminal boards, thus providing the Owner with an upgrade that enhances and achieves their best project cost and schedule.

As shown above, there are multiple different Series Upgrades  (200 and 400 Series) which encompass and allow us to upgrade most excitation systems found in the power generation industry. Below,  are some close-up pictures of what each Series control faceplate looks like and a brief summary of each.

IDP-801 Remote Touch Screen Monitor 

​               IN STOCK

Dual DECS-250 Upgrade Kit with IDP-801 Remote Touch Screen Monitor. Shipped loose components for custom integration into the existing panels, utilizing space available from obsolete components removed.

Turbine Diagnostic Service, Inc. (TDS) engineers are familiar with the excitation systems of small generators that are used on industrial units up to the large nuclear or fossil utility size generators. Many of the smaller generators utilize an Electric Machinery Rotating Exciter and OEM voltage regulator. Others use a buss fed static exciter. The TDS engineers have experience in steam and gas turbine generator systems ranging up to 1100 megawatts. Many of the larger generators incorporate a small A/C generator to supply the rectifiers of the generator exciter system, also known as an Alterrex. The newest of the large generators now utilize a P bar winding in the main generator to supply the power for the excitation system. TDS can service all these systems and their respective system power sources.

Our Phones are 24/7

Depending on your schedule, the Dual DECS-250/250N Upgrade Kit is available in Multiple Configurations. From a standard or custom pan chassis panel, pre-wired unit; to shipped loose individual components custom integrated into your existing panels utilizing the space available from the obsolete components removed. 

                                  EMERGENCY RESPONSE - Dual DECS-250 Kit - AVAILABLE NOW

TDS can provide upgrades for any type of excitation system. TDS’s engineers will design and install your selected excitation system upgrade KIT so that it enhances the Owner’s best project cost and schedule. The DECS-250 digital microprocessor voltage regulator is highly reliable in a single configuration as a stand alone controller with Auto and Manual Voltage Regulators. Should an Owner be looking for a simplified, economical solution, this single DECS-250 configuration option can be provided. The single and redundant dual DECS-250 KITS vary in complexity,  lead times and cost structures and can be provided with a Power System Stabilizer and Auto-Synchronizer. TDS can provide the DECS-250/250N on a planned upgrade basis with a pre-engineered system, or utilize the Single/Dual DECS-250 Shipped Loose Upgrade Kit maintained in stock at TDS (subject to prior sale) for emergency service response.