Allen-Bradley MPL Series Servo Motors

Technical Dossier

Product Details And Specifications

Allen-Bradley MPL Series Servo Motors: Comprehensive Module Range and Technical Overview

The Allen-Bradley MPL (Medium Power Low-inertia) Series, manufactured by Rockwell Automation, represents one of the most widely deployed servo motor families in global heavy industry. Installed across petrochemical refineries, nuclear power auxiliary systems, offshore drilling platforms, and continuous-process chemical plants, the MPL Series is the rotary motion backbone of Kinetix servo drive ecosystems. Its stainless-option variants and IP65/IP67-rated configurations make it a standard specification in washdown and hazardous-area environments. The series interfaces natively with Kinetix 5500, Kinetix 5700, Kinetix 6000, and Kinetix 6500 drive families via single-cable or dual-cable feedback architecture, and is catalogued under Rockwell's Integrated Motion on EtherNet/IP (IMC) framework.

The Evolution of MPL Series Architecture

The MPL Series was introduced as part of Rockwell Automation's transition from legacy 1326 and 1326AB servo motor platforms to the unified Kinetix motion control architecture in the early 2000s. Early MPL variants used resolver-based feedback (Bulletin 2090 resolver cables) and were paired with Ultra 3000 and Kinetix 6000 drives. As the platform matured, Rockwell introduced high-resolution multi-turn absolute encoders (2^20 counts/rev) and the single-cable feedback standard (2090-CSBM1DF), eliminating the separate encoder cable and reducing installation complexity.

The series is segmented by frame size (A through F), continuous stall torque rating, and feedback type. Voltage classes span 230 VAC and 460 VAC. The introduction of the Kinetix 5700 drive family extended MPL compatibility into the 460 VAC, high-power segment. Stainless steel shaft and housing variants (suffix -S) were added for food and pharmaceutical compliance. As of 2024, the MPL Series is in a mature/sustaining lifecycle phase; Rockwell Automation continues to manufacture and support the line, but new motion system designs are increasingly directed toward the VPL (Vertical Premium Low-inertia) and MPM (Medium Power Medium-inertia) series. For installed-base maintenance, long-term spare parts availability and repair support remain the primary procurement drivers.

MPL Series Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly stocked MPL Series servo motor models. Each entry reflects a distinct combination of frame size, continuous stall torque, speed rating, voltage class, and feedback type.

MPL-A310P-HK22AA: Frame A, 0.48 N·m stall torque, 460 VAC, resolver feedback, standard inertia.
MPL-A320P-HK22AA: Frame A, 0.96 N·m stall torque, 460 VAC, resolver feedback, standard inertia.
MPL-A330P-HK22AA: Frame A, 1.43 N·m stall torque, 460 VAC, resolver feedback, standard inertia.
MPL-A4530F-HJ72AA: Frame A, 1.43 N·m stall torque, 5000 RPM, 460 VAC, high-resolution encoder.
MPL-B310P-MK22AA: Frame B, 1.59 N·m stall torque, 460 VAC, resolver feedback, standard shaft.
MPL-B320P-MK22AA: Frame B, 3.18 N·m stall torque, 460 VAC, resolver feedback, standard shaft.
MPL-B330P-SJ72AA: Frame B, 4.78 N·m continuous stall torque, 230 VAC, high-resolution multi-turn absolute encoder, stainless steel shaft option, IP65 sealing — the subject SKU of this listing.
MPL-B330P-MK22AA: Frame B, 4.78 N·m stall torque, 460 VAC, resolver feedback, keyed shaft.
MPL-B4530F-MJ72AA: Frame B, 4.78 N·m stall torque, 5000 RPM, 460 VAC, high-resolution encoder.
MPL-B4560F-MJ72AA: Frame B, 4.78 N·m stall torque, 6000 RPM, 460 VAC, high-resolution encoder.
MPL-C4530F-SK22AA: Frame C, 7.63 N·m stall torque, 5000 RPM, 230 VAC, resolver feedback.
MPL-C4560F-SK72AA: Frame C, 7.63 N·m stall torque, 6000 RPM, 230 VAC, high-resolution encoder.
MPL-C4530F-HK22AA: Frame C, 7.63 N·m stall torque, 5000 RPM, 460 VAC, resolver feedback.
MPL-C4560F-HJ72AA: Frame C, 7.63 N·m stall torque, 6000 RPM, 460 VAC, high-resolution encoder.
MPL-D4530F-HK22AA: Frame D, 15.3 N·m stall torque, 5000 RPM, 460 VAC, resolver feedback.
MPL-D4560F-HJ72AA: Frame D, 15.3 N·m stall torque, 6000 RPM, 460 VAC, high-resolution encoder.
MPL-E4530F-HK22AA: Frame E, 30.5 N·m stall torque, 5000 RPM, 460 VAC, resolver feedback.
MPL-F4530F-HK22AA: Frame F, 61.0 N·m stall torque, 5000 RPM, 460 VAC, resolver feedback.

Sourcing Hard-to-Find & Obsolete MPL Series Parts

DriveKNMS maintains a dedicated inventory program for Allen-Bradley MPL Series servo motors, with particular focus on resolver-feedback variants (suffix -MK22AA, -HK22AA, -SK22AA) that are no longer in active production at Rockwell Automation distribution channels. As the MPL Series transitions into sustaining lifecycle status, procurement lead times through authorized distributors have extended to 16–26 weeks for non-stocked frames. DriveKNMS sources verified surplus and refurbished MPL units through a controlled supply chain, providing same-week dispatch for critical plant maintenance scenarios. All units are cross-referenced against Rockwell's published catalog numbers to confirm exact form-fit-function equivalence. Replacement feedback cables (Bulletin 2090-CSBM1DF, 2090-XXNFMF) and motor power cables (2090-CPWM7DF) are stocked in parallel to support complete drive-motor assembly replacement.

Quality Control for the MPL Series Range

Each MPL Series unit processed by DriveKNMS undergoes a structured inspection and functional verification protocol prior to dispatch. Mechanical inspection covers shaft runout (tolerance: ≤0.025 mm TIR), bearing play, encoder housing integrity, and connector pin condition on the 2090-series feedback and power connectors. Electrical verification includes winding resistance balance across all three phases (tolerance: ±5%), insulation resistance testing at 500 VDC (minimum 100 MΩ phase-to-ground), and back-EMF waveform symmetry check. For high-resolution encoder variants, the absolute position feedback signal is validated against a reference Kinetix drive axis configuration to confirm multi-turn data integrity and STO (Safe Torque Off) signal continuity. Resolver-feedback units are tested using a dedicated resolver excitation bench to verify transformation ratio and phase shift within Rockwell specification. Units that do not pass all checkpoints are quarantined and not offered for sale.