8 Tips To Protect Servo Motors from Electrical Surges

Servo motors are essential for precision motion control in industrial environments, including robotics, CNC machines, and automated production lines. Their accuracy, responsiveness, and ability to handle complex motion patterns make them the backbone of modern manufacturing. However, these motors are sensitive to electrical surges and anomalies, which can lead to catastrophic failures, production downtime, and expensive repairs. Protecting servo motors from such electrical disturbances is crucial to maintaining operational efficiency and minimizing costly disruptions.

Here are eight expert tips to ensure your servo motors remain protected:

1. Install surge protective devices (SPDs). SPDs are the first line of defense against electrical surges. Install these devices at the main electrical panel and at individual motor circuits. They divert excess voltage to grounding, protecting sensitive motor components from damage. Choose SPDs rated for your specific voltage and current requirements, and ensure they’re properly grounded for optimal performance.
2. Use proper grounding techniques. A robust grounding system is crucial for effective surge protection. Ensure all equipment — including servo motors, drive cabinets, and control panels — are properly grounded. Use low-impedance grounding cables and maintain clean, tight connections. Regularly inspect and test your grounding system to ensure its integrity.
3. Use isolation transformers. Isolation transformers provide an additional layer of protection by separating the servo motor circuit from the main power supply. They can block high-frequency noise and transient voltages, reducing the risk of surge-related damage. Choose transformers with adequate VA ratings and consider models with electrostatic shielding for enhanced protection against common-mode noise.
4. Employ power line filters. Power line filters help remove high-frequency noise and transients from the power supply. Install these filters between the power source and the servo drive to clean up the power signal. Look for filters with high insertion loss across a wide frequency range and ensure they’re rated for your system’s voltage and current requirements.
5. Utilize shielded cables. Shielded cables can reduce electromagnetic interference (EMI) and radio frequency interference (RFI), which can contribute to voltage spikes. Use high-quality shielded cables for power and signal connections to your servo motors. Also, be sure to maintain proper termination of cable shields at both ends and shield continuity throughout the system.
6. Implement soft-starting mechanisms. Soft starters or variable frequency drives (VFDs) can reduce inrush current during motor startup, minimizing the risk of voltage spikes. These devices gradually ramp up voltage and current, protecting both the motor and the power system from sudden surges. Choose soft starters or VFDs rated for your motor’s specifications and application requirements.
7. Power quality monitoring. Install power quality monitoring devices to track voltage fluctuations, harmonics, and other power anomalies. These systems can provide early warning of potential surge events and help identify the root causes of power quality issues. Use the data collected to implement targeted improvements in your surge protection strategy.
8. Implement redundant protection. Consider a layered approach to surge protection by installing multiple protective devices at different points in your electrical system. This redundancy ensures that if one protective measure fails, others are in place to prevent damage.

Implementing these protective measures not only ensures the longevity and reliability of your servo systems but also helps avoid costly downtime and repairs. With proper safeguards in place, your servo motors can continue to drive efficient and accurate motion control across a range of industrial applications.

SEASON SPECIAL: SERVO MOTOR REPAIRS

Dealing with servo motor damage? GES can help. Throughout the month of September, we’re excited to bring you incredible savings when it comes to servo motor repairs: 15% off three or more repairs or 10% off any single repair!