Servo Drive Module – HEIDENHAIN UM 114D
The UM 114D is an electronic servo drive module (“Servo Drive Module”) manufactured by HEIDENHAIN, designed to regulate axes or spindle within HEIDENHAIN CNC systems. It belongs to the family of power electronics modules used to drive and regulate servo motors (brushless and DC) within the CNC automation chain, interfacing with the main control unit via the proprietary HEIDENHAIN bus. The suffix D identifies a specific variant (e.g. rated voltage configuration or connector layout); the component may be present in different hardware revisions.
The drive module is the core of the axis regulation loop: it receives the position or speed reference from the numerical control and generates the drive current for the servo motor, ensuring positioning accuracy and stable dynamic response during machining. Without it the controlled axis is completely inert and the machine cannot execute any cycle; a fault typically manifests as position alarms, axis drifting, or immediate CNC program halt.
HEIDENHAIN (Dr. Johannes Heidenhain GmbH) is a German company founded in 1948 in Traunreut (Bavaria), a world leader in the production of high-precision linear and rotary measurement systems, TNC numerical controls, and drive modules for precision machine tools. The company remains privately and family-owned. Products in the UM series are legacy / discontinued: available exclusively as used, NOS (new old stock) or through specialist repair.
Main Technical Specifications
| Type | Servo drive module (Servo Drive Module) |
| Part number | UM 114D (UM114D) |
| Brand | HEIDENHAIN (Dr. Johannes Heidenhain GmbH) |
| Known application | HEIDENHAIN CNC systems (TNC series and legacy drives) |
| Function | Closed-loop current and speed regulation for axis/spindle |
| Logic supply | 24 V DC (typical) – verify specific revision documentation |
| Power supply | Three-phase or single-phase AC (typical) – hardware revision dependent |
| Compatible feedback | HEIDENHAIN encoder (linear/rotary), analogue tachogenerator |
| Interfaces / connectors | Proprietary HEIDENHAIN connectors; internal system bus |
| Weight | ~0.5–1.5 kg |
| Dimensions | ~150–280 mm |
| Production status | Legacy / discontinued — used/surplus/repair only |
Axis Drive Module – HEIDENHAIN UM 114
The UM 114 is an axis servo drive module (“Axis Drive Module”) manufactured by HEIDENHAIN, belonging to the modular drive family integrated into TNC-series CNC systems. The module manages the current and velocity regulation loops for brushless or DC servo motors connected to machine axes, interfacing with the control unit via the proprietary HEIDENHAIN bus. It is compatible with HEIDENHAIN encoders (resolver or incremental/absolute encoder). The commercial part number is UM 114.
The axis drive module is the electronic controller that closes the velocity and current loop on the axis servo motor: it receives the position/speed reference from the CNC unit and generates the current required to move the axis with precision and repeatability. Without it the axis cannot be controlled; any failure immediately halts the machine and makes machining impossible.
HEIDENHAIN is a German company founded in 1889, a world leader in the manufacture of linear and rotary encoders, CNC control systems (TNC series) and drives for high-precision machine tools. Products in the UM family belong to a historical generation of drives: legacy / discontinued, available exclusively as used, surplus or through specialist repair.
Main Technical Specifications
| Type | Axis servo drive module (Axis Drive Module) |
| Part number | UM 114 (UM114) |
| Brand | HEIDENHAIN (Dr. Johannes Heidenhain GmbH) |
| Known application | HEIDENHAIN TNC-series CNC systems (milling machines, machining centres, CNC grinders) |
| Function | Axis servo motor current and velocity regulation; control loop closure |
| Supply voltage | ~200–240 V AC, three-phase |
| Feedback | HEIDENHAIN incremental/absolute encoder or resolver |
| Control interface | Proprietary HEIDENHAIN bus; multi-pin / edge connectors |
| Output current | ~5–15 A |
| Weight | ~0.5–1.5 kg |
| Dimensions | ~150–250 mm |
| Production status | Legacy / discontinued — used/surplus/repair only |
Servo Axis Drive Module – HEIDENHAIN UE 211B
The UE 211B is a servo axis drive module (“Servo Axis Drive Module”) manufactured by HEIDENHAIN, belonging to the family of compact drive units designed for use with HEIDENHAIN TNC CNC controls (documented on TNC 155, TNC 355 systems and compatible variants). The module manages the current and speed regulation of a machine axis servo motor, interfacing with the CNC unit via HEIDENHAIN’s proprietary bus. The designation UE 211B identifies revision B of the 211 series; the unit is typically mounted inside the control cabinet or the machine’s drive assembly.
The servo axis drive module is the component that converts position and speed references from the CNC into drive current for the servo motor: it closes the current loop and contributes to the speed loop, ensuring the dynamic response required for precision machining. If it fails, the controlled axis becomes inoperative and the machine cannot perform any operations; replacement with an identical unit is often the only rapid solution, as these modules are not interchangeable with units of different series.
HEIDENHAIN is a German family-owned company founded in 1889, headquartered in Traunreut (Bavaria), and a world leader in the manufacture of linear and angular measurement systems, rotary encoders, and high-precision CNC controls for machine tools. The UE series modules belong to a legacy generation of drives: legacy / discontinued, available exclusively through the used market, industrial surplus, or specialist repair services.
Main Technical Specifications
| Type | Servo axis drive module |
| Part number | UE 211B (UE211B) |
| Brand | HEIDENHAIN |
| Known application | CNC machine tools with HEIDENHAIN TNC control (TNC 155, TNC 355 and compatible variants) |
| Function | Servo motor current and speed regulation for axis drive |
| Supply | ~24 V DC logic; DC bus from centralised power supply module |
| Rated power | ~1–3 kW |
| Interfaces | Proprietary HEIDENHAIN bus; multi-pin connectors for motor and encoder feedback signals |
| Weight | ~0.8–2.0 kg |
| Dimensions | ~200–300 × 100–150 mm |
| Production status | Legacy / discontinued — used/surplus/repair only |