Paragon reverse engineered English Electric turbine control circuit cards for a U.S. nuclear power plant.

Our reverse engineered units have the same form, fit, and function as the originals and can be installed in the original English Electric card cages with no modifications.


The reverse engineered units were designed to be drop-in replacements that required no field work at the power plant. The circuit boards were all built to the original unit dimensions and fit up was verified in the original card cages. Test jack locations were maintained in similar locations as the original so there would be no learning curve for maintenance or operations personnel.

The traces on the circuit boards were routed as close to the original design as possible to reduce and/or eliminate any EMI/RFI risks. Any deviations due to component obsolescence were documented indicating the replacement had retained the same form, fit, and function as the original component. All circuit boards were manufactured to IPC-610, Class 2 Specifications.


Paragon had previous experience performing emergent repairs for this system. When the customer pursued a proactive reverse engineering solution for obsolescence, Paragon used that experience to develop a thorough testing program. All units were functionally tested based on the critical design characteristics of that unit, developed from the original design, industry OPEX, and site procedures.

The Paragon English Electric turbine control circuit cards are fit, form, and functionally equivalent to the original units. They can interface directly with the existing system components and operate in accordance with existing plant operating procedures.

Part Numbers

The part numbers below have been reverse engineered by Paragon and are available for manufacture. Click on each part number to link to the Paragon Catalog.

Part Number


650-30X-3153/ATC LVDT Driver
650-30X-3154/ATC Comparator and Relay Board
650-30X-3156/ATC Averaging Circuit & Gain Amplifier
650-30X-3157/ATC Power Amplifier
650-30X-3159/ATC Function Generator
650-30X-3161P10/ATC Relay Plug In
A512-A026/ATC Inverting Amplifier