Key Technical Specifications
| Parameter | Value |
|---|---|
| Model | MAC112C-0-ED-2-C/130-B-0 |
| Manufacturer | Indramat / Bosch Rexroth |
| Product Type | Three-Phase AC Servo Motor |
| Product Series | MAC112 |
| Origin | Germany |
| Mounting | Flange mount (C-type configuration) |
| Dimensional Spec | 130mm related |
| Application Domain | CNC machines, automation lines, packaging/printing equipment, material handling |
| Compatible Drives | Indramat/Rexroth servo drives (HDS, DKC series, etc.) |
| Condition | Obsolete / Surplus stock |
Product Introduction
I’ve pulled more than a few of these out of machine cabinets over the years. The Indramat MAC112 series was the workhorse servo motor on European-built automation equipment throughout the 1990s and early 2000s. This specific model — MAC112C-0-ED-2-C/130-B-0 — is a flange-mounted, three-phase AC servo motor built for precision motion control applications: CNC feed axes, automated assembly stations, printing presses, anywhere you need repeatable positioning under load.What made the MAC112 series stick around for so long was its tight integration with Indramat’s servo drive ecosystem. The encoder feedback, commutation logic, and thermal protection were all designed as a matched set with drives like the HDS and DKC families. That pairing gave you predictable dynamic response and reliable thermal behavior during continuous duty cycles. The trade-off? This motor is firmly a legacy product now. Indramat got absorbed into Rexroth, and the MAC platform has been superseded by newer motor lines. But if you’re keeping a 20-year-old machine running, finding the right MAC112 variant is still the fastest path back to production.
Quality SOP & Tech Pitfalls
The Lab Report (SOP)
Here’s what needs to happen before this motor ships out:
- Visual/Counterfeit Inspection: Confirm Indramat/Rexroth branding and full model number (MAC112C-0-ED-2-C/130-B-0) on the nameplate. Look for signs of relabeling or tampered markings.
- Mechanical Inspection: Check the housing for cracks or impact damage. Spin the shaft by hand — it should rotate freely with no grinding, binding, or bearing noise. Inspect the flange face and keyway for wear.
- Insulation Resistance Test: Use a megohmmeter to measure winding-to-ground insulation resistance. Anything below spec is a dead motor.
- Winding Resistance Test: Measure DC resistance across all three phases. They should read balanced. An open or shorted phase means the motor is scrap.
- Encoder Check: If equipped with an encoder, inspect the connector and signal wiring for damage or corrosion.
- Protective Packaging: Install shaft end caps, wrap in shock-absorbing material, and seal for shipment.
The Engineer’s Warning (Pitfalls)
- Trusting the frame size alone. The MAC112 designation tells you the physical envelope. It does not tell you the encoder type, brake configuration, shaft keyway dimensions, or winding characteristics. I once watched a maintenance crew spend two days trying to commission a “replacement” MAC112 that had the right frame but the wrong encoder output — the drive threw commutation faults every time they enabled the axis. Match the full part number, every character.
- Skipping the encoder compatibility check. The encoder resolution, signal format (incremental vs. absolute), and interface protocol must match what your servo drive expects. A mismatch here won’t just cause an alarm — it can cause the motor to run in the wrong direction or oscillate violently at startup. Verify encoder specs against your drive’s configuration before powering anything up.
Installation & Configuration Guide
- Pre-Installation (⚠️ Safety First)
- Lock out and tag out all power sources — both the main bus and the servo drive control supply.
- Confirm zero-energy state with a calibrated multimeter.
- Photograph the existing motor’s wiring connections, encoder cable routing, and mechanical mounting orientation. This step alone has saved me hours of reverse-engineering on the floor.
- Removal
- Label every cable: U/V/W power leads, encoder connector, and brake leads if present.
- Disconnect all cables.
- Loosen and remove the flange mounting bolts.
- Carefully extract the motor from the mechanical assembly, supporting the load to prevent it from dropping.
- Installation
- Before mounting, inspect the new motor’s shaft keyway, flange face, and sealing surfaces for shipping damage.
- Align the motor to the mounting position. Confirm coupling or传动 mechanism alignment within tolerance.
- Install and tighten flange bolts to the OEM-specified torque value, using a cross-pattern sequence.
- Reconnect power cables (U/V/W in correct phase sequence) and encoder cable.
- Power-On & Verification
- Restore control power only. Verify the drive recognizes the motor parameters (model, encoder config).
- Run at low speed. Watch for abnormal vibration, noise, or direction errors.
- Ramp up to operating speed gradually. Verify positioning accuracy and dynamic response.
- Execute a full production cycle before releasing the machine back to operations.
Compatible Replacement Models
| Model | Compatibility Tier | Notes |
|---|---|---|
| MAC112C-0-ED-2-C/130-B-0 | ✅ Drop-in Replacement | Same part number — direct swap; verify encoder config matches your drive |
| MAC112C series (different suffixes) | ⚠️ Verify with OEM | Same frame size but encoder, brake, or shaft config may differ — compare full part numbers character by character |
| Rexroth MSK/MKD series | ⚠️ System modification required | Newer platform with better performance specs, but mechanical interfaces and drive protocols differ — expect rewiring and reconfiguration |
| Third-party servo motors | ❌ Hardware mod required | Different mounting dimensions, encoder protocols, and drive compatibility — not recommended as a direct substitute |
Frequently Asked Questions (FAQ)
Q: What do the different segments of the MAC112C model code actually mean?
Each segment in the part number encodes a specific configuration parameter — frame size, mounting style, encoder type, brake presence, shaft form, and special options. The exact mapping can vary across production periods, so I’d recommend pulling the Indramat/Rexroth motor selection manual for the definitive decoding table rather than guessing.Q: Can I still buy this motor brand new?
Unlikely. The MAC series is a legacy Indramat product line and has been discontinued for years. What you’ll find on the market is surplus stock — either new-old-stock (NOS) pulled from warehouse inventory or used/refurbished units. Ask the supplier for the actual condition and any test documentation before you commit.Q: What happens if I install a MAC112 with the wrong encoder type?
The drive won’t be able to commutate the motor correctly. You’ll see one of three things: the motor won’t move at all, it’ll oscillate or vibrate without rotating, or it’ll spin in the wrong direction. In the worst case, a severe encoder mismatch can damage the drive’s feedback input stage. Don’t assume “it’s still a MAC112 so it’ll work.”Q: My motor hums but doesn’t rotate after installation. What’s wrong?
Three things to check first: (1) encoder cable — is it seated fully and are the pins clean? (2) power phase sequence — U/V/W swapped even one position and the motor won’t commutate. (3) drive parameter setup — does the drive have the correct motor model and encoder resolution programmed? Fix those three and you’ll solve this 9 times out of 10.Q: Which servo drives are compatible with this motor?
The MAC112 series was designed to pair with Indramat/Rexroth servo drives, primarily the HDS and DKC families. The exact drive model depends on your motor’s encoder type and the control mode you need. Check the Rexroth product compatibility documentation for the specific pairing, or ask your supplier to cross-reference your drive model against the motor’s full part number.
