Surge Protective Device
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Difference Between Lightning Arresters and Surge Arresters
Understanding the difference between Surge Arresters and Lightning Arresters is crucial for protecting electrical systems. Lightning strikes are frequent — according to the UK’s weather department, over 3 million lightning flashes occur every day worldwide, averaging about 44 strikes per second. Protecting buildings and electrical equipment from these events requires properly designed devices.
This article explains the differences, applications, and key points for Surge Arresters and Lightning Arresters.
Lightning Arrester
A Lightning Arrester is used to reduce and eliminate lightning risks. When lightning strikes, it releases a large amount of energy in a few seconds, which can damage buildings and electrical systems. Lightning Arresters protect by providing a low-resistance path to ground, safely diverting the charge.
Types of Lightning Arresters
- Conventional Lightning Arresters (Franklin Rods)
Suitable for small buildings. Long metallic rods, often made of copper, are installed at the highest points. Requires multiple rods, additional down conductors, and complex earthing for larger structures. - Early Streamer Emission (ESE) Lightning Arresters
Designed to discharge lightning faster and cover larger areas. Works by emitting charged particles and storing energy from the ambient electromagnetic field. A single ESE arrester can protect a larger area compared to conventional rods.
Installation Recommendations
- Place at the highest point of the building.
- Connect to a low-resistance grounding system.
- Use multiple devices for larger areas to ensure full coverage.
Applications
Residential homes, commercial buildings, industrial facilities, and power substations.
Where are Surge Arrester
Surge Arresters protect internal electrical systems from overvoltages. They usually use Metal Oxide Varistors (MOVs), which vary resistance with voltage to absorb or divert surges.
Types of Overvoltage Surges
- Normal Power Frequency Overvoltage: Temporary spikes from faulty wiring, sudden power restoration, or overloads.
- Lightning Surge: Caused by nearby lightning strikes.
- Switching Surge: Generated from opening or closing high-voltage lines or switching inductive/capacitive loads.
Installation Locations
- Electrical substations at feeder entrances.
- Around power transformers to protect high-value equipment.
- Within pad-mounted transformers, domestic circuit breakers, and riser poles.
Note: Do not confuse Surge Arresters with Surge Protectors (SPDs), which are for low-voltage home appliances. SPDs also use MOVs but are designed to protect home wiring and appliances from voltage spikes.
Key Differences Between Surge Arresters and Lightning Arresters
| Feature | Surge Arrester | Lightning Arrester |
|---|---|---|
| Protection Target | Internal electrical systems | External structures and associated components |
| Working Principle | Uses MOV to absorb/dissipate overvoltage | Attracts lightning and diverts it to ground |
| Protection Scope | Lightning surges, switching operations, transient voltages | Primarily lightning strikes |
| Installation | Substations, transformers, distribution panels | Building tops, industrial structures, critical external points |
Selection Guidelines
- Small Buildings & Residential Homes: Conventional Lightning Rods + basic Surge Arrester.
- Large Industrial Facilities: ESE Lightning Arresters + high-capacity Surge Arresters.
- High-Value Equipment: Combine SPDs with MOV-based Surge Arresters for comprehensive protection.
Tip: Proper installation, grounding, and periodic maintenance are critical to ensure the devices work as intended.
Our Products and Services
At GA&DA Electric, we provide high-quality electrical protection devices for all your needs:
- Lightning Arresters (ESE & Conventional)
- Metal Oxide Surge Arresters
- Surge Protection Devices (SPDs) for home and industrial use
- Engineering support for design, installation, and maintenance
Contact us today: https://cngandian.com/contact
FAQ – Surge Arrester & Lightning Arrester
Can a Lightning Arrester protect internal electrical equipment?
Lightning Arresters are primarily designed to protect buildings and external structures from direct lightning strikes. To protect internal electrical systems, you should install Surge Arresters or SPDs at strategic points like transformers, distribution panels, or sensitive equipment.
Can Surge Arresters prevent damage from direct lightning strikes?
No, Surge Arresters are designed to handle overvoltages caused by lightning-induced surges, switching operations, or transient spikes. Direct lightning strikes require Lightning Arresters for safe grounding.
How do I choose between a conventional Lightning Rod and an ESE Lightning Arrester?
Conventional rods are suitable for small buildings with simple protection needs. ESE (Early Streamer Emission) devices cover larger areas and are ideal for industrial buildings, factories, or commercial complexes where fewer units can provide broader coverage.
Do SPDs (Surge Protection Devices) replace Surge Arresters?
No, SPDs are for low-voltage applications and protect appliances in homes or small offices. Surge Arresters protect medium/high-voltage electrical systems and are used in substations or industrial distribution setups.
How often should Lightning and Surge Arresters be inspected?
It is recommended to inspect them at least once a year or after any severe storm. Check for physical damage, corrosion, grounding integrity, and proper mounting.
