NSK EXEA1 Series AC Servo Drives

Technical Dossier

Product Details And Specifications

NSK EXEA1 Series: Comprehensive Module Range and Technical Overview

The NSK EXEA1 series is a line of compact AC servo drives engineered for precision motion control in demanding industrial environments. Deployed extensively across chemical processing plants, semiconductor fabrication facilities, automotive assembly lines, and heavy-duty machine tool applications, the EXEA1 platform has established a significant installed base in Asia-Pacific and European manufacturing sectors. Its architecture supports single-axis servo control with integrated regenerative braking circuits, making it a standard specification in coordinated multi-axis CNC and robotic workcell designs. The series interfaces directly with NSK Megatorque and ball screw actuator systems, providing a tightly coupled motion solution that reduces integration complexity in OEM machine builds.

The Evolution of EXEA1 Architecture

The EXEA1 series was introduced as NSK's second-generation digital servo amplifier platform, succeeding the earlier ESA and ESAC analog drive families. The transition from analog to full digital current-loop control in the EXEA1 brought sub-millisecond position loop update rates and eliminated the manual gain potentiometer adjustments required on predecessor units. Early EXEA1 variants used a parallel 50-pin I/O interface for host controller communication; later revisions introduced optional serial encoder feedback compatibility and expanded fault diagnostic registers accessible via RS-232C. The series operates on a 200–230 V AC single-phase or three-phase input and covers output current ratings from 1.0 A to 30 A continuous, spanning a motor capacity range of approximately 50 W to 3 kW. As of the mid-2010s, NSK transitioned its servo drive portfolio toward the ESMC and ESA2 platforms, placing the EXEA1 series in end-of-life status. Installed units remain in active service across legacy machine populations, and long-term maintenance support is the primary procurement driver for this series today. Compatibility between EXEA1 amplifiers and NSK S-MEGA, M-MEGA, and RA series servo motors is documented in NSK application note AN-EXEA1-COMPAT-R3.

EXEA1 Full Catalog & Functionalities (SKU List)

The following SKUs represent the documented EXEA1 series production range, classified by output current rating and configuration variant. Each unit is a single-axis AC servo amplifier unless otherwise noted.

EXEA1-0010A01-03: 1.0 A continuous output, 200 VAC single-phase input, standard I/O interface, 50 W motor class.
EXEA1-0020A01-03: 2.0 A continuous output, 200 VAC single-phase, incremental encoder feedback, 100 W motor class.
EXEA1-0030A01-03: 3.0 A continuous output, 200 VAC single/three-phase, regenerative resistor terminal, 200 W motor class.
EXEA1-0050A01-03: 5.0 A continuous output, 200 VAC three-phase, expanded fault log, 400 W motor class.
EXEA1-0075A01-03: 7.5 A continuous output, 200 VAC three-phase, dynamic brake circuit, 750 W motor class.
EXEA1-0100A01-03: 10.0 A continuous output, 200 VAC three-phase, full regenerative unit, 1.0 kW motor class.
EXEA1-0150A01-03: 15.0 A continuous output, 200 VAC three-phase, high-inertia load tuning preset, 1.5 kW motor class.
EXEA1-0200A01-03: 20.0 A continuous output, 200 VAC three-phase, extended I/O option slot, 2.0 kW motor class.
EXEA1-0300A01-03: 30.0 A continuous output, 200 VAC three-phase, large-frame chassis, 3.0 kW motor class.
EXEA1-0010A02-03: 1.0 A output, 100 VAC single-phase input variant, 50 W motor class, Japan domestic market specification.
EXEA1-0020A02-03: 2.0 A output, 100 VAC single-phase input variant, 100 W motor class, Japan domestic market specification.
EXEA1-0030A02-03: 3.0 A output, 100 VAC single-phase input variant, 200 W motor class, Japan domestic market specification.
EXEA1-0050A02-03: 5.0 A output, 100 VAC three-phase input variant, 400 W motor class, Japan domestic market specification.
EXEA1-0100A02-03: 10.0 A output, 100 VAC three-phase input variant, 1.0 kW motor class, Japan domestic market specification.
EXEA1-0200A02-03: 20.0 A output, 100 VAC three-phase input variant, 2.0 kW motor class, Japan domestic market specification.
EXEA1-0300A02-03: 30.0 A output, 100 VAC three-phase input variant, 3.0 kW motor class, Japan domestic market specification.

Sourcing Hard-to-Find & Obsolete EXEA1 Parts

The EXEA1 series reached official end-of-production status, and NSK no longer manufactures replacement units or spare PCB assemblies through standard distribution channels. For operators of legacy machine tools, semiconductor handlers, and precision assembly systems still running EXEA1 amplifiers, unplanned drive failure creates immediate production risk. DriveKNMS maintains a dedicated inventory of tested EXEA1 units sourced from decommissioned equipment, overstock liquidations, and authorized refurbishment pipelines. Stock coverage includes both the A01 (200 VAC) and A02 (100 VAC) input variants across the full current rating range. Units are held in climate-controlled storage and dispatched with full traceability documentation. For customers requiring a direct cross-reference to current NSK servo platforms, DriveKNMS technical staff can provide application-specific migration guidance from EXEA1 to ESA2 or ESMC series equivalents, including parameter mapping tables and wiring adaptation notes.

Quality Control for the EXEA1 Range

Each EXEA1 unit processed by DriveKNMS undergoes a structured multi-stage verification protocol before dispatch. The procedure begins with visual inspection of the power stage IGBT module, DC bus capacitor bank, and gate driver PCB for physical damage, electrolyte leakage, or thermal stress indicators. Functional testing is performed on a dedicated servo drive test bench using a matched NSK servo motor load, replicating the rated continuous and peak current profiles specified in the EXEA1 hardware manual. Position loop closure is verified at 1 kHz update rate with encoder signal integrity confirmed via oscilloscope capture. Fault code registers are cleared and re-exercised through simulated overcurrent, overvoltage, encoder loss, and regenerative overload conditions to confirm correct protective response. Units that pass all test stages are assigned a DriveKNMS QC serial number and shipped with a test report summary. Units that fail any stage are quarantined and not offered for sale.