Industrial Cable Assemblies factory

How to Protect Industrial Cables from Surges

In industrial environments, electrical surges pose a significant threat to industrial cables. These sudden, brief spikes in voltage can originate from various sources—such as lightning strikes, power grid fluctuations, or the startup and shutdown of high-power equipment like motors or transformers. When surges travel through industrial cables, they can damage the cable insulation, disrupt signal transmission, and even lead to costly downtime of connected machinery. Protecting industrial cables from surges is not just about preserving the cables themselves; it is a critical step in ensuring the overall reliability and safety of industrial operations. Below are practical, actionable strategies to achieve this protection.

1. Establish a Robust Grounding System

A proper grounding system is the first line of defense against electrical surges. It provides a low-resistance path for surge currents to dissipate into the ground, preventing them from flowing through industrial cables and damaging equipment.

• Use dedicated grounding conductors: For industrial cables, especially those carrying high voltage or critical signals, pair them with dedicated grounding wires. These conductors should be made of high-conductivity materials (e.g., copper) and have a cross-sectional area matching the cable’s current capacity to handle surge currents effectively.
• Maintain low grounding resistance: Ensure the grounding system’s resistance is kept below 5 ohms (a common industry standard for industrial settings). Regularly test the grounding resistance using a clamp-on ground tester, and clean or repair corroded grounding connections to avoid resistance buildup.
• Adopt a star grounding topology: In areas with multiple cables or equipment, use a star (radial) grounding design. This design connects all cables and equipment to a single, central grounding point, preventing surge currents from “bouncing” between different grounding paths and damaging cables.

2. Install Suitable Surge Protective Devices (SPDs)

SPDs are designed to divert excess surge current away from cables and equipment. Choosing and installing the right SPDs is key to effective surge protection.

• Select SPDs based on surge type and voltage rating: Industrial environments may face different surge types (e.g., lightning-induced surges, switching surges). For cables connected to power lines, use Type 1 SPDs (for lightning protection at the service entrance) and Type 2 SPDs (for secondary protection near equipment). For signal cables (e.g., Ethernet or control cables), use Type 3 SPDs, which are designed for low-voltage, high-frequency signals.
• Install SPDs close to cable entry points: Mount SPDs as close as possible to where cables enter the facility or equipment. This minimizes the length of cable exposed to surge currents before the SPD can divert them. For example, install SPDs at the main electrical panel for power cables, and near control boxes for signal cables.
• Regularly inspect and replace SPDs: SPDs degrade over time after absorbing surges. Check SPDs monthly for indicator lights (most have a “normal” or “fault” light) and replace any SPD that shows signs of damage (e.g., bulging, burnt marks) or has reached its service life (typically 3–5 years).

3. Choose Surge-Resistant Industrial Cables

The type of cable used directly impacts its ability to withstand surges. Investing in surge-resistant cables reduces the risk of insulation breakdown and signal loss.

• Opt for cables with thick, durable insulation: Look for industrial cables with insulation made of materials like cross-linked polyethylene (XLPE) or ethylene propylene rubber (EPR). These materials have high dielectric strength, meaning they can withstand higher voltage spikes without breaking down.
• Select shielded cables for signal protection: For control or communication cables, use shielded cables (e.g., twisted pair with foil or braid shielding). The shield acts as a barrier, blocking external electromagnetic interference (EMI) that often accompanies surges and preventing it from disrupting signal transmission.
• Avoid undersized cables: Undersized cables generate more heat during normal operation, which weakens their insulation over time. A weakened insulation is more likely to fail during a surge. Always choose cables with a current-carrying capacity that exceeds the maximum current of the connected equipment.

4. Implement Routine Cable Maintenance and Monitoring

Regular maintenance helps identify potential vulnerabilities before surges cause damage, ensuring cables remain protected long-term.

• Conduct visual inspections: Every 3–6 months, inspect industrial cables for signs of wear, such as cracked insulation, loose connections, or exposure to harsh elements (e.g., water, chemicals). Replace any damaged cables immediately, as compromised insulation is far more susceptible to surge damage.
• Monitor cable temperature and current: Use IoT-based sensors (e.g., thermal sensors, current transformers) to monitor the real-time temperature and current of critical cables. Abnormal temperature spikes or current fluctuations can indicate insulation degradation or impending surge risks, allowing for proactive repairs.
• Keep cables away from surge-prone areas: Route industrial cables away from high-risk zones, such as near lightning rods, power transformers, or large motors. If routing near these areas is unavoidable, use cable trays with metal shielding to add an extra layer of protection.

Conclusion

Protecting industrial cables from surges requires a combination of proactive design, quality components, and regular maintenance. By establishing a strong grounding system, installing appropriate SPDs, selecting surge-resistant cables, and implementing routine checks, industrial facilities can significantly reduce the risk of cable damage, equipment failure, and production downtime.

When it comes to safeguarding your industrial cables and operations against surges, FRS brand factory stands as a trusted partner. We specialize in providing comprehensive industrial cable protection solutions, including high-quality surge-resistant cables, industry-compliant SPDs, and custom grounding system components. Our products are engineered to meet the rigorous demands of industrial environments, ensuring long-lasting durability and reliable surge protection. Whether you need to upgrade existing cables, install SPDs, or design a full surge protection scheme, FRS works closely with you to deliver solutions tailored to your specific needs—keeping your operations running smoothly and securely.