Bosch Rexroth PL20 Series Servo Drives — PL20B-D

Technical Dossier

Product Details And Specifications

Bosch Rexroth PL20 Series: Comprehensive Module Range and Technical Overview

The Bosch Rexroth PL20 series represents a compact, single-axis servo drive platform engineered for precision motion control in demanding industrial environments. Deployed extensively across chemical processing plants, oil refineries, nuclear facility auxiliary systems, and heavy-duty manufacturing lines, the PL20 family occupies a critical position in legacy and mid-generation Rexroth drive architectures. Its modular design, compatibility with SERCOS and analog command interfaces, and robust DC bus architecture made it a standard specification in European and Asian heavy industry installations throughout the 1990s and 2000s. Many facilities continue to operate PL20-based motion systems as part of long-term capital equipment strategies, making reliable spare parts sourcing a persistent operational requirement.

The Evolution of PL20 Architecture

The PL20 series was introduced as part of Rexroth's Diax and Ecodrive-adjacent compact drive family, targeting single-axis applications where the full Diax04 or IndraDrive platform was over-specified. Early variants used analog ±10V velocity command inputs with resolver feedback, establishing a straightforward integration path for legacy CNC and PLC controllers. Mid-generation revisions introduced digital encoder support (TTL/HTL incremental) and expanded the power range from the base B-frame (PL20B) to larger current ratings. The PL20 series interfaces with Rexroth MKD, MKE, and MSK motor families via standard power and feedback connectors. As the IndraDrive Cs (HCS01) and IndraDrive Mi (KSM/KMS) platforms matured in the 2010s, PL20 entered end-of-life status. Rexroth's recommended migration path leads to the IndraDrive Cs HCS01.1E series, which offers backward-compatible motor support with modern fieldbus integration (PROFINET, EtherCAT, SERCOS III). Facilities still running PL20 hardware must source replacement units from specialist distributors, as OEM new-stock availability is effectively exhausted.

PL20 Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly sourced models within the Bosch Rexroth PL20 series. Units are classified by frame size, current rating, and feedback/interface variant.

Compact Single-Axis Servo Drives — B-Frame (Low Power)

• PL20B-D: Compact single-axis servo drive, analog command, resolver feedback, B-frame
• PL20B-D-01: B-frame drive, variant 01, enhanced EMC filter integrated
• PL20B-D-02: B-frame drive, variant 02, extended temperature range rating
• PL20B-T: B-frame, TTL incremental encoder feedback, ±10V command input
• PL20B-T-01: B-frame TTL variant, UL-listed configuration for North American market

Compact Single-Axis Servo Drives — C-Frame (Mid Power)

• PL20C-D: C-frame single-axis drive, resolver feedback, higher continuous current rating
• PL20C-D-01: C-frame, variant 01, integrated braking resistor circuit
• PL20C-T: C-frame, TTL encoder feedback, analog velocity command
• PL20C-T-02: C-frame TTL, variant 02, CE-marked, 400V AC input nominal
• PL20C-S: C-frame, SERCOS I/II digital interface, position control mode

Compact Single-Axis Servo Drives — D-Frame (Higher Power)

• PL20D-D: D-frame resolver-feedback drive, higher peak current, 400V three-phase
• PL20D-T: D-frame TTL encoder variant, suitable for high-inertia load applications
• PL20D-S: D-frame SERCOS interface, synchronized multi-axis coordination capable
• PL20D-S-01: D-frame SERCOS, variant 01, extended I/O terminal block configuration

Power Supply / Regenerative Units (PL20 Compatible)

• PL20-NTZ: DC bus power supply unit, compatible with PL20 B/C/D frame drives, regenerative capable

Sourcing Hard-to-Find & Obsolete PL20 Parts

The Bosch Rexroth PL20 series reached end-of-production status, and OEM factory-new inventory is no longer available through standard distribution channels. DriveKNMS maintains a dedicated inventory of tested PL20 units sourced from decommissioned machinery, controlled factory shutdowns, and verified surplus channels across Europe, Japan, and North America. All units are catalogued by frame size, feedback type, and firmware revision where applicable. For facilities operating under long-term maintenance contracts or ISO 55000 asset management frameworks, DriveKNMS provides condition-verified exchange units with documented test records. Customers requiring specific firmware versions or hardware revisions for compatibility with existing Rexroth IndraControl or third-party CNC controllers are encouraged to specify requirements at the time of inquiry. Lead times for low-volume PL20 variants (D-frame SERCOS) are typically 2–4 weeks subject to stock rotation.

Quality Control for the PL20 Range

Each PL20 unit processed by DriveKNMS undergoes a structured inspection and functional test protocol prior to dispatch. The procedure addresses the specific failure modes documented in the PL20 field service history: DC bus capacitor degradation, IGBT gate driver circuit faults, resolver signal conditioning board failures, and control board EEPROM parameter corruption. Functional testing is performed under load using matched Rexroth MKD or MSK motor test beds at rated speed and torque. SERCOS-interface variants are verified for ring communication integrity and parameter download capability. Analog-command variants are tested across the full ±10V input range with velocity linearity verification. Units exhibiting parameter loss or non-recoverable firmware faults are quarantined and not offered for resale. Test records are available upon request for critical infrastructure procurement processes.