Lightning Surge Troubleshooting: How to Protect Industrial Equipment from High-Voltage Surges
Key Takeaways
- Lightning surges can introduce dangerous high voltages and currents into industrial systems.
- Both direct lightning strikes and nearby lightning activity can damage equipment or cause system malfunctions.
- Surge protection devices such as arresters, varistors, and spark quenchers can help reduce the impact of lightning-related voltage spikes.
- Proper surge protection can improve reliability and reduce unexpected downtime.
- Protection methods should always be validated on the actual equipment and installation environment.
What Is a Lightning Surge?
Have you ever experienced unexpected equipment failures, communication interruptions, or control system malfunctions after a thunderstorm?
The cause may be a lightning surge.
A lightning surge is a temporary high-voltage event caused by lightning. When lightning strikes nearby power lines, utility poles, buildings, or the surrounding area, a large electrical surge can travel through connected wiring and equipment.
There are two common types of lightning surges:
Direct Lightning Surges
A direct lightning surge occurs when lightning strikes equipment such as:
- Power poles
- Antennas
- Electrical infrastructure
- Building power systems
These events can introduce extremely high voltages into the connected system.
Induced Lightning Surges
Lightning does not need to strike equipment directly to cause problems.
When lightning strikes near a facility, electromagnetic energy can induce a surge into nearby wiring, resulting in voltage spikes that may affect electronic devices and industrial controls
Common Symptoms of Lightning Surge Damage
Lightning-related electrical surges can cause a wide range of issues throughout an automation system.
Common symptoms include:
Sensor Failures
- Sudden sensor damage
- Intermittent operation
- Unstable outputs
PLC and Control Issues
- Unexpected resets
- Communication interruptions
- Fault conditions
- Input and output errors
Equipment Damage
- Power supply failures
- Damaged control components
- Burned communication devices
Intermittent System Performance
In some cases, a lightning surge may weaken components without causing immediate failure. This can lead to recurring issues that are difficult to diagnose.
Why Industrial Facilities Are Vulnerable
Modern manufacturing equipment often includes:
- Sensors
- PLCs
- Servo systems
- HMI devices
- Network communication equipment
- Power supplies
These devices are interconnected through power and communication wiring, creating pathways through which surge energy can travel.
Even facilities that have never experienced a direct lightning strike may encounter induced surges during nearby storms.
As automation systems become increasingly interconnected, surge protection becomes an important part of maintaining system reliability.
Lightning Surge Protection Devices
Several protection devices are commonly used to reduce the effects of lightning surges and other high-voltage events.
The guide evaluated the effectiveness of several surge protection components:
- Spark quenchers
- Varistors
- Arresters
Each device works differently to minimize the impact of excessive voltage
Solution 1: Use a Varistor to Suppress Excess Voltage
A varistor is designed to react when voltage exceeds a specific threshold.
When excessive voltage is detected, the varistor begins conducting current to limit the voltage seen by connected devices.
This helps suppress dangerous voltage spikes before they reach sensitive electronics.
Benefits of Varistors
- Reduces voltage spikes
- Protects connected equipment
- Simple installation in many applications
- Effective for surge suppression
Testing showed that a varistor can effectively suppress over-voltage conditions compared to systems without protection.
Solution 2: Install an Arrester
An arrester provides another layer of protection against lightning-related events.
When voltage exceeds a predefined level, the arrester diverts excess energy away from the device and safely directs it toward ground.
This prevents damaging voltages from reaching critical equipment.
Benefits of Arresters
- Diverts surge energy to ground
- Protects sensitive electronics
- Commonly used in industrial environments
- Helps reduce equipment damage during surge events
The testing demonstrated that arresters effectively redirect over-voltage conditions away from protected systems
Solution 3: Consider Spark Quenchers
Spark quenchers help suppress sudden voltage changes by gradually dissipating stored electrical energy.
Their effectiveness depends on the specific application and surge conditions.
In the testing referenced by the guide, spark quenchers showed limited improvement for the lightning surge scenario evaluated. However, they are still commonly used as part of broader surge protection strategies.
Troubleshooting Checklist for Lightning Surge Issues
If you suspect a lightning surge may be causing equipment problems, work through the following steps:
Review Recent Weather Events
- Have storms occurred recently?
- Was lightning reported near the facility?
- Did issues begin shortly after a storm?
Inspect Vulnerable Equipment
Check:
- Sensors
- PLCs
- Communication devices
- Power supplies
- Network infrastructure
Verify Grounding Systems
- Ensure grounding connections are secure.
- Confirm grounding systems meet facility requirements.
Evaluate Existing Surge Protection
- Are arresters installed?
- Are varistors being used?
- Are surge protection devices functioning properly?
Test the System
Monitor equipment performance and compare operation before and after implementing surge protection measures.
Because every installation environment is different, performance improvements should always be validated on the actual equipment.
Protect Your Automation System Before the Next Storm
Lightning surges can create serious reliability issues in industrial environments, even when lightning never directly strikes the facility.
By implementing proper surge protection devices such as arresters and varistors, manufacturers can help protect sensitive electronics from damaging voltage spikes. Combined with effective grounding and system design practices, these measures can reduce downtime, prevent equipment damage, and improve long-term system reliability.
Whether you are troubleshooting recurring failures or designing a new automation system, surge protection should be considered a critical part of your overall electrical protection strategy.
Frequently Asked Questions about Lightning Surges
Q Can lightning damage equipment without a direct strike?
A
Yes. Nearby lightning activity can generate induced surges that travel through power and communication wiring, potentially affecting connected equipment.
Q What equipment is most vulnerable to lightning surges?
A
Sensors, PLCs, communication devices, power supplies, and other electronic control components are commonly affected by surge events.
Q What is the difference between a varistor and an arrester?
A
A varistor suppresses excessive voltage by conducting current when a threshold is reached. An arrester redirects excessive voltage safely to ground.
Q Are lightning surges only a concern during storms?
A
No. Industrial environments may also experience high-voltage surge events from other electrical sources, although lightning is one of the most common causes.
Q Is surge protection guaranteed to prevent damage?
A
No protection method eliminates all risk. The effectiveness of surge protection depends on the installation, equipment, grounding, and environmental conditions.
