smigroup LAFERT B7108Q-03326 Brushless Servo Motor

Description

3. Key Technical Specifications

4. Product Introduction

The smigroup LAFERT B7108Q-03326 is a brushless AC servo motor designed for precision industrial automation applications. Manufactured by Lafert—an Italian specialist in servo motor technology—and distributed through smigroup, this motor delivers high-torque performance in a compact 142mm square flange package. It is commonly deployed in packaging machinery, material handling systems, CNC equipment, and automated production lines requiring precise motion control.This servo motor provides 8.0 Nm stall torque and 7.0 Nm rated torque at 2000 RPM, making it suitable for medium-duty applications requiring smooth, accurate positioning. The B71 frame size (142mm square flange) and 8-pole design (indicated by “Q” in the model code) ensure high dynamic response and stable operation across variable load conditions. While Lafert has discontinued this specific model, it remains critical for maintaining legacy automation systems where direct mechanical and electrical compatibility is required.

5. Installation & Configuration Guide

Stage 1: Pre-Installation Preparation (15 minutes)

⚠️ Safety First: Notify operations of planned downtime. Verify the machinery is in a safe state. Lock out/tag out (LOTO) all power sources to the servo drive and motor. Wait 5 minutes for capacitor discharge in the drive before handling any connections.Tools Required:

• ESD wrist strap (grounded)
• Metric hex key set (for flange mounting)
• Torque wrench
• Digital multimeter (Fluke 115 or equivalent)
• Wire labeling tape or markers
• Smartphone/camera (for documentation)

Data Backup:

• Record current drive parameters (motor type, encoder resolution, current limits)
• Document mechanical mounting dimensions and coupling alignment
• Photograph all wiring connections (power, feedback, thermal) before removal

Stage 2: Removing the Old Motor (10 minutes)

1. Remove any guarding or protective covers.
2. Disconnect all wiring: Power (U/V/W), Feedback (resolver/encoder), Thermal protection (if fitted), Brake (if fitted). Label each cable.
3. Loosen the flange mounting bolts in a diagonal pattern to avoid stressing the housing.
4. Carefully slide the motor shaft out of the coupling/gearbox. Support the motor weight—do not let it hang on the shaft.
5. Inspect the coupling, gearbox input, and mounting surface for wear or damage.
6. ⚠️ Note: Keep the old motor for reference until the new one is running perfectly. Do not discard until commissioning is complete.

Stage 3: Installing the New Motor (12 minutes)

1. ESD prep: Verify your wrist strap is properly grounded.
2. Mechanical Installation:
   • Verify shaft alignment with the driven equipment (coupling or gearbox). Misalignment causes bearing failure and vibration.
   • Mount the motor using proper torque on flange bolts (typically 8-12 Nm for M8 bolts—verify with datasheet).
   • Ensure free rotation by hand before applying power.
3. Electrical Connections:
   • Connect power leads (U, V, W) to the servo drive output. Verify phase sequence matches the old motor.
   • Connect feedback device (resolver or encoder) using the correct cable and pinout.
   • Connect thermal protection (KTY or PTC) if present.
4. Configuration:
   • Enter motor parameters into the servo drive: Rated current (3.3A), Rated speed (2000 RPM), Torque constant, Encoder type/resolution.
   • Set current limits appropriate for 8.0 Nm peak torque.

Self-Checklist:

• [ ] Shaft alignment verified (within 0.05mm TIR)
• [ ] All bolts torqued to specification
• [ ] Power phases correctly sequenced
• [ ] Feedback cable securely connected and shielded
• [ ] Thermal protection wired (if applicable)
• [ ] Motor rotates freely by hand

Stage 4: Power-On & Testing (13 minutes)

Pre-Power Check: Use your multimeter to verify:

• No shorts between motor phases (U-V, V-W, W-U)
• No ground faults (each phase to ground)
• Correct DC bus voltage at the drive

Power-On Steps:

1. Apply control power only (main power off). Verify drive initializes without faults.
2. Apply main power. Observe drive and motor status:
   • No alarm codes = Good
   • Encoder fault = Check feedback cable and parameter setting
   • Overcurrent = Check wiring and mechanical binding
3. Run a low-speed jog test (100-200 RPM). Listen for abnormal noise or vibration.
4. Verify encoder count direction matches commanded direction (positive = clockwise or per your convention).
5. Run a torque verification test at rated load if possible.
6. Commission into full automatic operation gradually.

⚠️ Troubleshooting Note: If the drive reports “Motor Overload” or “Encoder Error,” verify:

• Motor parameters match the B7108Q-03326 specifications exactly
• Feedback device type (resolver vs. encoder) matches your drive configuration
• Mechanical load is not seized or overloaded

B7108Q-03326

6. Frequently Asked Questions (FAQ)

Q: Is the B7108Q-03326 still manufactured, and is your stock genuinely new?A: No, this motor is officially discontinued by Lafert. Our inventory consists of new surplus stock—units manufactured during the original production run but never deployed. These are factory-sealed or tested units stored in climate-controlled conditions. We also offer refurbished units that have undergone full functional testing. Each unit ships with a detailed test report and warranty (1-2 years depending on condition).Q: What does the model code “B7108Q-03326” mean?A: The Lafert model code breaks down as follows:

• B71 = Motor size (142mm square flange)
• 08 = Torque rating (8 Nm class)
• Q = Speed rating (3000 rpm series—though this unit is 2000 RPM, likely a variant)
• 3 = Voltage code
• H = 380/400V (may vary by configuration)
• 4 = Connection type
• A = Without brake, keyed shaft
• 05 = Resolver feedback (2-pole)
• 0 = Cooling (natural convection)
• 0 = Connection direction (standard)
• 00 = Special options (none)

Q: What is the direct replacement if the B7108Q-03326 is out of stock?A: Compatible alternatives within the same series include:

• B7108P-03177 (similar 8Nm class, different winding)
• B7116Q-03323 (16Nm variant for higher torque requirements)
• B7128Q-03325 (28Nm variant)

For new designs, Lafert recommends their current B71 series or Ultra Compact series motors. However, these may require mechanical and electrical adaptation. Contact us with your application requirements for cross-reference verification.Q: Can I use this motor with any servo drive?A: No. The B7108Q-03326 requires a servo drive compatible with:

• 296 VDC bus voltage
• 3.3A continuous current rating
• Resolver or incremental encoder feedback (depending on your specific unit configuration)
• Sinusoidal commutation for brushless motors

Common compatible drives include smigroup’s own servo drive series, or third-party drives properly parameterized for Lafert motor characteristics. Never connect to a VFD (Variable Frequency Drive) designed for induction motors—this will destroy the motor.Q: Why is your price lower than the OEM factory list price?A: Lafert no longer manufactures this part, so “factory list price” is largely academic. Our pricing reflects the new surplus market reality—unused inventory acquired from plant closures, system upgrades, and distributor liquidations. We test every unit and pass the savings from bypassing traditional distribution channels directly to you. You’re buying proven hardware at market rates, not paying inflated prices for obsolete catalog listings.Q: Does this motor include a brake?A: No. The B7108Q-03326 is configured without brake. If your application requires holding torque when power is removed, you must add an external brake or select a different model variant. The “-A” in the model code indicates “without brake, keyed shaft”. For brake-equipped versions, look for model codes containing brake designators (typically “B” or specific brake suffixes).Q: What maintenance does this brushless servo motor require?A: Brushless servo motors are generally maintenance-free for the electromagnetic components. However, periodic inspection is recommended:

• Check bearing noise and temperature annually
• Verify encoder/resolver cable integrity
• Inspect shaft seals for contamination ingress
• Ensure cooling vents (if fitted) remain unobstructed

The bearings are pre-lubricated and sealed for life. If bearing replacement becomes necessary, it requires specialized equipment to maintain encoder alignment—typically performed by factory-authorized service centers.