Description

REXROTH Servo Motor MSK101D-0200-NN-M1-AG0-NNNN — Full Introduction

This is a IndraDyn S series synchronous servo motor from Bosch Rexroth (Germany), belonging to the MSK sub-series. It is designed for high-torque, medium-to-low-speed industrial automation applications that demand exceptional precision, rigidity, and dynamic response.

1. Model Code Decoding

The model number follows Rexroth’s standard naming convention. Each segment carries specific meaning:

MSK — IndraDyn S series synchronous servo motor family.

101 — Frame size. The 101 series is a large frame in the MSK lineup, with a flange diameter of approximately 140 mm. This puts it in the high-torque class.

D — Motor length code. In the MSK101 family, the length grades go A → B → C → D → E. “D” is a medium-long version — longer than C but shorter than E — delivering medium-to-high torque output.

0200 — Rated speed of 2,000 rpm. This is a low-to-medium speed variant, optimized for maximum torque delivery rather than top speed.

NN — Cooling method: natural convection (no external fan, no liquid cooling). Simple, maintenance-free design.

M1 — Encoder type: EnDat 2.2 absolute multi-turn encoder. High-precision feedback device that retains position data even after power loss — no homing required on restart.

AG0 — Electrical connection: rotatable plug connector (240° rotation). The “G0” suffix means no holding brake (no抱闸). The motor shaft freewheels when power is removed.

NNNN — Standard design, no special customization.

2. Core Technical Parameters

Based on the MSK101D series specifications and the 0200 speed variant, the typical performance data for this motor is as follows:

Rated speed: 2,000 rpm (as specified in the model code)

Maximum speed: Up to approximately 4,600 rpm (MSK series general limit, roughly 2.3× rated speed)

Rated torque (continuous, standstill / M0): Approximately 50 Nm — this is the key selling point of the 101D frame

Maximum torque (peak, short-term / Mmax): Approximately 160 Nm

Rated current (continuous / I0): Approximately 22.2 A

Peak current (Imax): Approximately 99.9 A

Torque constant (Kt): Approximately 2.26 Nm/A

Voltage constant (Ke): Approximately 9.55 V/(1000 rpm)

Rotor inertia (J): Approximately 0.00932 kg·m² — moderate for the 101 class, lower than the 101E variant

Thermal time constant: Approximately 45–60 minutes (large frame, high thermal mass)

Protection class: IP65 — fully sealed against dust and low-pressure water jets. Suitable for CNC machine environments with coolant spray, oil mist, metal chips, etc.

Insulation class: F class (155°C)

Weight: Approximately 18–22 kg (motor body only, no brake — because AG0 = no holding brake)

⚠️ Key data comparison from Rexroth official datasheets:

Model	M0 (Rated Torque)	Mmax (Peak Torque)	J (Inertia)
MSK101C-0200	~32 Nm	~110 Nm	0.0065 kg·m²
MSK101D-0200 (this model)	~50 Nm	~160 Nm	0.00932 kg·m²
MSK101E-0200	~70 Nm	~231 Nm	0.0138 kg·m²

As you can see, MSK101D sits right in the sweet spot of the 101 series — enough torque for heavy-duty applications, but with significantly lower inertia than the 101E. This makes it the best value-for-performance choice in the 101 family for most applications.

3. Key Features and Advantages

1. Ultra-high torque density — the “muscle” of the MSK 101 family

The MSK101D delivers 50 Nm continuous torque and 160 Nm peak torque in a 140 mm flange package. This is among the highest torque densities in its class. It is ideal for driving heavy loads and high-inertia mechanical axes such as: large CNC machine feed axes, injection molding clamp units, heavy robot joints, and press feed mechanisms.

2. EnDat 2.2 absolute multi-turn encoder — zero homing, zero position loss

The M1 encoder uses the EnDat 2.2 protocol, with 2048 lines per single turn + multi-turn counting. This means:

• Sub-micron level positioning accuracy
• Position data is permanently retained even after complete power loss
• No homing sequence needed on every startup — the drive always knows the exact shaft position
• This saves significant cycle time and improves overall system reliability

3. 2,000 rpm rated speed — the perfect torque + speed balance

Compared to the 0300 (3,000 rpm) or 0450 (4,500 rpm) high-speed variants, the 0200 speed grade dedicates more of the electromagnetic design space to torque. This makes MSK101D-0200 the ideal choice for heavy cutting at moderate feed rates — exactly what large CNC machines and pressing equipment need.

4. IP65 protection — built for the harshest industrial environments

Fully sealed construction with shaft seals protects the motor from dust, metal chips, coolant spray, oil mist, and water jets. It can operate reliably in CNC machining centers, injection molding machines, stamping presses, and other demanding industrial settings without any additional protective measures.

5. No holding brake (AG0) — designed for horizontal axes

Since “G0” means no holding brake, the motor shaft is free to rotate when de-energized. This makes it perfect for:

• ✅ Horizontal axis applications (e.g., X/Y feed axes on CNC machines) — the load won’t fall or drift when power is cut
• ✅ Systems with external braking mechanisms (e.g., hydraulic clamps, pneumatic brakes)
• ❌ NOT suitable for vertical axes (Z-axis) — for vertical lifting, you must choose a model with UP0/UP1 (with brake)

6. Rotatable plug connector (240°) — installation made easy

The electrical connector can be rotated 240°, so you don’t need to precisely align the plug direction during installation. This greatly simplifies on-site wiring and motor replacement/maintenance.

7. Natural convection cooling — zero maintenance

No external fan, no liquid cooling loop. The motor dissipates heat through its own housing. Fewer components, lower installation cost, and zero maintenance for the cooling system.

4. Typical Application Scenarios

5. Comparison with Similar Models in the Same Series

6. Recommended Drive System Pairing

The MSK101D-0200-NN-M1-AG0-NNNN is co-engineered with Rexroth’s IndraDrive Cs / IndraDrive C servo drive families, but is also compatible with other drives that support the EnDat protocol. Recommended pairings:

Supported communication protocols: PROFINET, EtherCAT, EtherNet/IP, PROFIBUS, SERCOS III, CANopen — virtually all major industrial fieldbuses are covered.

7. Summary

The MSK101D-0200-NN-M1-AG0-NNNN is a 2,000 rpm, 50 Nm continuous torque, 160 Nm peak torque, EnDat 2.2 absolute multi-turn encoder, naturally cooled, IP65-rated, no holding brake large-frame synchronous servo motor from Bosch Rexroth.

It represents the optimal torque-to-inertia balance in the MSK 101 series — making it one of the best value-for-performance choices in its class. It is especially well-suited for:

• ✅ Applications requiring high torque + medium speed for heavy loads
• ✅ High-precision scenarios that demand no position loss and zero homing
• ✅ Horizontal axis installations or systems with external braking
• ✅ Harsh industrial environments with oil mist, coolant, dust, and metal chips

⚠️ If your application is a Z-axis (vertical lifting), you MUST choose the UP0/UP1 version with a holding brake. If you need higher speed, consider the 0300 or 0450 rpm variants instead.