Many industrial plants are still running DC motors with legacy SCR drive systems that were installed before AC VFDs became the standard. When a Reliance FlexPak, an Allen-Bradley 1395, or a Mentor II fails, the path to replacement is not a catalog order. It's a sourcing call. Send us the drive model and what failed.
A significant number of industrial plants, paper mills, plastics processors, and metal fabrication facilities continue to operate DC drive systems installed in the 1980s and 1990s. The motors themselves run for decades with minimal maintenance. The SCR drive systems feeding them are more fragile: boards fail, SCR modules fail, and the drive platforms themselves are long discontinued.
When a firing board trips and won't come back, or an SCR module fails and the plant goes down, the options are limited. The original manufacturer either no longer exists or no longer supports the product line. Third-party repair shops exist, but sometimes the board is beyond repair and needs a replacement, and sometimes a facility needs a spare drive on the shelf before the primary fails completely.
Edmundson Industrial sources legacy DC drives and SCR drive components. We look for complete drive units (for shelf spares or direct replacement), individual boards (firing boards, armature feedback cards, field supply boards), and power components (SCR modules, rectifier bridges, gate drivers). Condition is disclosed on every quote.
The Reliance FlexPak 3000 and GP2000 are among the most widely installed legacy DC drives in North American industry. Reliance was acquired by Rockwell, and these drive lines were discontinued. Boards, fuses, and complete spare units are sourced through the secondary market.
The Allen-Bradley 1395 is a well-known DC SCR drive platform used in heavy industrial applications. Like the 1391, it has been discontinued and is no longer supported by Rockwell Automation. Spare boards and complete units are sourced through surplus and specialty inventory.
Magnetek produced both AC and DC drive systems across multiple product families. The DC drive lines are discontinued. Specific board and component requests require the drive model number and the component description or board number from the drive's documentation.
Eurotherm drives (later branded SSD, then acquired by Parker) produced a widely installed family of DC drives across multiple size ranges. Older units in the 590 and 605 families are discontinued. Boards and replacement drives sourced as available through specialty channels.
The Mentor II and Mentor MP are Control Techniques DC drive platforms used heavily in industrial and oilfield applications. Boards for these drives are specific to the platform and are sought frequently for repair and spare inventory purposes.
Minarik and Fincor produced smaller DC drive controllers used across a wide range of process and machine tool applications. These platforms are discontinued and parts come from surplus inventory. Model number and board part number are needed for identification.
For drives that are repairable but need a specific board or power component rather than a complete replacement unit.
SCR modules for three-phase and single-phase DC drives. Ratings must match the original unit exactly: voltage blocking, on-state current, and case style. Single SCR, dual SCR, and bridge pack configurations sourced. Cross-reference to the module part number printed on the original.
SCR firing boards generate the gate pulses that control the SCR conduction angle. Gate driver cards condition those pulses for the power stage. Both are platform-specific and are frequently the failure point in an aging drive. Board part number or drive model is required.
Armature feedback boards measure and regulate the motor armature voltage in closed-loop DC drives. Field supply boards regulate field current. Snubber boards protect the SCR devices from voltage transients. All are platform-specific; cross-reference required.
The drive model number and the board or component part number are the starting point. For complete drive requests, the horsepower rating, armature voltage, and armature current (from the motor nameplate) help confirm that a sourced unit is appropriate for the application.
Use the RFQ form or email directly. Include the drive model and the specific component needed. Photos of the nameplate and failed component are always helpful.