The Rexroth R911315803 MSK100C-0300-NN-M2-AG0-RNNN is a high-precision synchronous servo motor from the IndraDyn S MSK product family, designed for industrial automation systems that require stable torque output, reliable absolute feedback, and consistent mechanical running accuracy. This exact order number is associated with the full type code MSK100C-0300-NN-M2-AG0-RNNN, and distributor references identify it as a natural-convection servo motor with a multi-turn EnDat 2.1 encoder, side-A connector arrangement, plain shaft with shaft sealing ring, no holding brake, and a special design version with increased concentricity.
Unlike a generic industrial motor, this model belongs to a configurable servo platform where each section of the code defines a real mechanical or electrical feature. That is why the complete designation matters in purchasing, replacement, and technical documentation. For industrial users, the value of this motor is not only in its torque and speed performance, but also in its configuration accuracy. In servo applications, an incorrect encoder type, shaft execution, or connection side can create integration problems even when the frame size appears correct. The full code R911315803 MSK100C-0300-NN-M2-AG0-RNNN therefore serves as the key product identifier for both engineering and procurement work.
Product Overview
| Item | Description |
|---|---|
| Brand | Rexroth |
| Order Number | R911315803 |
| Full Model | MSK100C-0300-NN-M2-AG0-RNNN |
| Product Family | IndraDyn S MSK |
| Product Type | Synchronous servo motor |
| Cooling Method | Natural convection |
| Encoder Type | Multi-turn EnDat 2.1 encoder |
| Encoder Resolution | 2,048 signal periods with 4,096 revolutions absolute |
| Power Connection | Side A |
| Shaft Version | Plain shaft with shaft sealing ring |
| Holding Brake | No |
| Special Design | Increased concentricity |
| Net Weight | 45.1 kg |
| Protection Class | IP65 |
| Insulation Class | 155 |
| Maximum Speed | 4500 rpm |
| Maximum Torque | 148 Nm |
The summary above combines the exact model references with the official MSK100C-0300-NN technical platform data. The weight of 45.1 kg is the correct working figure for the non-brake version, because the technical data show 45.1 kg for the standard configuration and 50.0 kg in brackets for brake-equipped variants. Since this exact motor is coded AG0, meaning no holding brake, the lower figure applies to this model.
Type Code Interpretation
| Code Section | Meaning |
|---|---|
| MSK | IndraDyn S synchronous servo motor series |
| 100 | Frame size 100 |
| C | Motor length C |
| 0300 | Winding code 0300 |
| NN | Natural convection cooling |
| M2 | Multi-turn EnDat 2.1 encoder |
| A | Power connection on side A |
| G | Plain shaft with shaft sealing ring |
| 0 | Without holding brake |
| RNNN | Design with increased concentricity |
This code structure is important because the motor is built for exact specification rather than broad category matching. The M2 option identifies a multi-turn EnDat 2.1 encoder, and one distributor reference describes it as offering 2,048 signal periods with 4,096 revolutions absolute. The RNNN suffix is also not cosmetic; Rexroth type-code documentation defines it as a design with increased concentricity, which indicates a version selected for better running accuracy and tighter mechanical quality in applications where shaft concentricity matters.
Technical Data
| Parameter | Value |
|---|---|
| Continuous torque at standstill, 60 K | 38.0 Nm |
| Continuous current at standstill, 60 K | 21.6 A |
| Continuous torque at standstill, 100 K | 43.5 Nm |
| Continuous current at standstill, 100 K | 27.0 A |
| Continuous torque at standstill, surface cooled | 57.0 Nm |
| Continuous current at standstill, surface cooled | 32.4 A |
| Maximum torque | 148.0 Nm |
| Maximum current | 97.2 A |
| Torque constant at 20 °C | 1.94 Nm/A |
| Voltage constant at 20 °C | 119.1 V/1000 rpm |
| Winding resistance at 20 °C | 0.30 ohm |
| Winding inductivity | 4.200 mH |
| Number of pole pairs | 4 |
| Rotor inertia | 0.02730 kg·m² |
| Thermal time constant | 90.0 min |
| Maximum speed | 4500 rpm |
| Sound pressure level | <75 dB(A) |
| Ambient operating temperature | 0 to 40 °C |
| Protection class | IP65 |
| Insulation class | 155 |
| Weight, no brake | 45.1 kg |
These technical values come from the MSK100C-0300-NN technical data and define the real performance profile of the motor. They place the unit in the medium-to-large servo range, with enough continuous torque for serious industrial axis work and enough peak torque for dynamic acceleration, speed changes, and intermittent overload conditions. The combination of 38.0 Nm continuous standstill torque and 148.0 Nm maximum torque makes this motor suitable for machines that must maintain controlled motion under changing process loads rather than simply rotate at constant speed.
Mechanical and Motion-Control Value
One of the most important characteristics of the Rexroth R911315803 is that it combines absolute feedback capability with a mechanically refined design. The M2 multi-turn EnDat 2.1 encoder is attractive in systems where axis position must remain known across multiple revolutions and where restart behavior or homing efficiency matters. In real machine operation, that can reduce setup time and improve position awareness compared with simpler feedback arrangements. This makes the motor particularly relevant to precision machinery, transfer axes, packaging equipment, CNC-related motion systems, and robotic handling modules.
The RNNN design with increased concentricity is another reason this motor stands apart from standard variants. In automation systems that depend on high running smoothness, precise coupling alignment, or strict mechanical quality at the shaft end, increased concentricity can be a meaningful specification rather than a minor option. It is especially relevant in applications involving high positional accuracy, repeated cycle stability, and reduced vibration transfer into connected mechanical assemblies. For buyers and engineers, this means the motor is not just a standard MSK100C platform unit, but a more specialized version aimed at tighter mechanical performance.
The no-brake AG0 configuration also has practical significance. A servo motor without holding brake is often the right choice for horizontal axes, continuously supported drive systems, or machine designs where external mechanical retention is already provided. Removing the brake simplifies the configuration, avoids unnecessary weight increase, and keeps the motor aligned with installations that were originally designed without a brake. In this case, that also supports the 45.1 kg weight figure rather than the heavier brake-equipped alternative shown in the technical tables.
Application Perspective
| Application Area | Why This Motor Fits |
|---|---|
| CNC machinery | High torque capability with precise multi-turn feedback |
| Packaging equipment | Good for repeated acceleration, indexing, and controlled stops |
| Material handling systems | Absolute encoder feedback improves position reliability |
| Transfer and positioning axes | Increased concentricity supports precision mechanical running |
| Printing and converting machines | Stable speed control and smooth shaft execution |
| Industrial retrofit projects | Exact Rexroth configuration helps reduce replacement risk |
From an application standpoint, this motor is best used where accuracy, feedback quality, and mechanical stability must be considered together. It is not merely a power upgrade over smaller servos; it is a configuration-specific motor intended for demanding motion systems. The 4500 rpm maximum speed allows flexible operation across a broad motion range, while the IP65 protection class supports use in normal industrial environments where dust resistance and enclosure quality matter. The insulation class 155 and 90-minute thermal time constant also reinforce its suitability for sustained industrial duty rather than occasional use.
Weight and Installation Considerations
The product weight of approximately 45.1 kg should be included in commercial descriptions because it is relevant to transport planning, installation handling, mounting design, and service preparation. In practice, weight affects freight cost estimation, bracket verification, replacement logistics, and the method used for on-site handling. Since this exact version is a non-brake model, 45.1 kg is the appropriate technical reference. Using the brake-equipped figure would overstate the physical configuration of the actual AG0 motor.
For OEM builders, this weight is substantial enough to indicate a serious industrial-duty servo, yet still practical within the structural range of many machine frames. For maintenance teams, it is heavy enough to require realistic handling preparation but not so large that it moves into an uncommon installation class. This balance makes the motor suitable for both new equipment integration and exact spare-part replacement in established Rexroth-based systems.
Why This Exact Part Number Matters in Procurement
Industrial customers typically do not search only for “Rexroth servo motor.” They search for the exact order number and full type code because that is the safest method of avoiding mismatch. Terms such as “R911315803,” “MSK100C-0300-NN-M2-AG0-RNNN,” and “Rexroth MSK100C multi-turn EnDat servo motor” are far more useful in purchasing and technical review than broad family names alone. A product page that clearly states the encoder type, shaft execution, connection side, brake status, technical values, and product weight is therefore more useful to both search engines and actual industrial buyers.
Conclusion
The Rexroth R911315803 MSK100C-0300-NN-M2-AG0-RNNN is a precision-configured IndraDyn S synchronous servo motor for demanding industrial motion applications. Its exact specification combines natural convection cooling, a multi-turn EnDat 2.1 encoder, side-A power connection, a plain shaft with shaft sealing ring, no holding brake, and a special increased-concentricity design. Official MSK100C-0300-NN technical data show 38.0 Nm continuous standstill torque, 148.0 Nm maximum torque, 4500 rpm maximum speed, IP65 protection, and a non-brake weight of 45.1 kg. For CNC equipment, packaging machinery, handling systems, and exact replacement work, this model is a strong option when configuration accuracy is as important as servo performance.
