What is the Difference Between a Surge Diverter and a Surge Arrester?

Surge protection is crucial in safeguarding electrical and electronic devices from voltage surges or transient overvoltages that can cause damage or malfunction. Two commonly used devices for surge protection are surge diverters and surge arresters. In this article, we will explore the key differences between these two devices and their respective functions in protecting against electrical surges.

I. Surge Arresters: Understanding Their Role

A surge arrester, also known as a lightning arrester or transient voltage suppressor, is an essential component in electrical systems designed to protect against voltage surges. It works by diverting excessive voltage to the ground, thereby safeguarding sensitive equipment. Surge arresters are primarily used in high-voltage applications and come in various types, such as zinc oxide surge arresters and silicone rubber surge arresters.

Zinc Oxide Surge Arresters:

Zinc oxide surge arresters are commonly used in high-voltage transmission and distribution systems. They rely on metal oxide varistors (MOVs) as their key component. When a voltage surge occurs, the MOVs in the surge arrester become conductive, providing a low-impedance path for the surge current to flow to the ground. This effectively limits the voltage across connected equipment and protects them from damage.

Silicone Rubber Surge Arresters:

Silicone rubber surge arresters are another type of surge arrester that offers excellent protection against voltage surges. These arresters utilize silicone rubber as an insulating material, making them suitable for outdoor and harsh environmental conditions. Like zinc oxide surge arresters, silicone rubber surge arresters also use MOVs to divert surge currents safely.

II. Surge Diverters: Their Function and Characteristics

Surge diverters, also known as surge protectors or surge suppressors, are critical components in electrical systems that serve the primary function of safeguarding sensitive equipment and circuits from voltage surges or transient overvoltages. They do so by absorbing and redirecting the excess energy away from the protected devices, preventing damage and ensuring the continuous operation of electrical systems. Here, we will delve deeper into their function and explore the key characteristics that make surge diverters indispensable in surge protection.

Function of Surge Diverters:

The primary role of surge diverters is to mitigate the effects of voltage surges by providing a low-resistance path for the excess electrical energy to dissipate harmlessly. When a voltage surge occurs, surge diverters become conductive, effectively diverting the surge current away from the protected equipment. This process ensures that the voltage levels at the downstream devices remain within safe limits, preventing damage to sensitive electronics and electrical systems.

Characteristics of Surge Diverters:

Voltage Rating: Surge diverters are available in various voltage ratings to suit different applications. It's essential to choose a surge diverter with a voltage rating that matches or exceeds the voltage levels present in the electrical system to ensure effective protection.

Response Time: Surge diverters are designed to respond rapidly to voltage surges. Their quick response time is crucial in diverting the surge energy before it can reach and harm connected devices. In most cases, surge diverters respond in nanoseconds, providing near-instantaneous protection.

Components: Surge diverters typically incorporate components like metal oxide varistors (MOVs) and capacitors. MOVs are essential for clamping the excess voltage, while capacitors help absorb and dissipate the surge energy. The combination of these components ensures effective surge suppression.

Installation Location: Surge diverters are commonly installed at the point of entry of electrical circuits, where power enters a building or facility. Placing them here ensures that voltage surges are intercepted before they can propagate through the building's wiring, offering comprehensive protection to all connected devices.

Maintenance: Surge diverters are relatively low-maintenance devices. However, periodic inspections and testing are recommended to ensure they remain in optimal working condition. If a surge diverter sustains damage or loses its effectiveness, it should be promptly replaced to maintain surge protection.

Environmental Durability: Surge diverters are often exposed to outdoor conditions, so they are designed to withstand harsh environments. Many surge diverters feature weather-resistant enclosures and materials like silicone rubber to ensure long-term durability.

Cost-Effective Protection: One of the significant advantages of surge diverters is their cost-effectiveness. They provide reliable surge protection at a fraction of the cost of other surge protection devices, making them a practical choice for many applications.

III. Key Differences Between Surge Arresters and Surge Diverters

While both surge arresters and surge diverters offer surge protection, there are fundamental differences between the two:

Function:

Surge Arresters: Divert excessive voltage to the ground, protecting connected equipment.

Surge Diverters: Absorb and dissipate transient overvoltages before they reach sensitive devices.

Components:

Surge Arresters: Utilize components like MOVs for voltage diversion.

Surge Diverters: Incorporate metal oxide varistors (MOVs) and capacitors for voltage absorption.

Application:

Surge Arresters: Commonly used in high-voltage applications and power distribution systems.

Surge Diverters: Installed at the entry points of electrical circuits in buildings and facilities.

In summary, surge arresters and surge diverters play distinct roles in protecting electrical and electronic equipment from voltage surges. Surge arresters are primarily designed to divert excessive voltage to the ground, while surge diverters absorb and dissipate transient overvoltages. Understanding these differences is essential for selecting the right surge protection device for specific applications, ensuring the reliable operation of electrical systems and the protection of valuable equipment.