What Is Surge Protection: Guide to Surge Protective Device (SPD)

One of the most crucial things nowadays is protecting your electronic devices from power surges. But how can you protect your electrical systems? You can do so by using surge protection devices. An appropriate SPD will protect your electrical systems and devices from transient voltage, preventing costly downtime.

In this guide, we are going to look into the basics of surge protection, their working principle, types, and the components and factors central to their performance. Moreover, we’ll look into how to choose the right surge protection device for your needs. 

What is Surge Protection & What is a Surge Protection Device?

Surge protection basically means protecting electrical equipment from unexpected voltage spikes. This is done using a device called a surge protector or a surge suppressor, which protects your electrical equipment from transient overvoltage. Many factors, including lightning strikes, power outages, or switching operations within the electrical grid, can be the reason behind overvoltage. 

Causes of Electrical Surges

Various factors can cause electrical surges, including:

• Lightning strikes are one of the major causes behind electrical surges. Although a direct strike to the power line can cause massive damage, a strike miles away can also cause surges in the power grid. 
• Everyday activities, such as turning on and off high-voltage devices like an air-conditioner, can also cause a power surge. 
• Overloaded outlets or circuits are also a cause of electrical surges. 
• Damaged or exposed wiring is another factor that causes electrical surges, as the electricity flowing through them is not directed or handled the way it normally should be. 
• Sudden loss and restoration of power can also cause voltage spikes. 

What Does a Surge Protector Do?

The main purpose of a surge protective device is to limit the overvoltage and bring it to a safer level to protect the control systems and electrical equipment. By managing the voltage, a surge protector reduces the maintenance cost and downtime of your devices.

Wondering how does a surge protector work? A Surge protector consists of voltage limiting and voltage switching components. The Metal Oxide Varistors (MOVs) and Transient Voltage Suppression (TVS) Diodes are the voltage-limiting components while the Gas Discharge Tubes and spark gaps are the voltage-switching components. These components react to voltage spikes, diverting or limiting surge current to the ground or back to its source. 

In order to work, an SPD should have a non-linear component that can transition between high and low-impedance states.

If the voltage is normal, the SPD would be at a high-impedance state and would not affect the system. When a voltage spike occurs, the SPD transitions to a low impedance state and diverts or limits the surge current back to the ground or the source, clamping the voltage to a safer level. Once the overvoltage is diverted, the SPD returns to its high-impedance state. 

Components of Surge Protective Devices

• Metal Oxide Varistors (MOVs): A type of resistor that is applied in series, which changes its resistance based on the voltage applied to it. In case of a power surge, it directs the extra voltage away from the electrical systems.
• Gas Discharge Tubes: This is basically a sealed container with ionized gas inside. This ionized gas protects against high-voltage surges, letting them pass through safely. 
• Transient Voltage Suppression Diodes: This component clamps the excess voltage and protects the devices against surges. 

If you are looking for a high end surge protective device, visit Go Switchgear today. The Surge Protection Device AC 3 Pole Type 2 580V Imax 40kA SPDAC23rb is ideal for protecting control panels from internal surges, and protects the higher-voltage industrial setups. It has the ability to handle upto 40kA, which mean your sensitive electronics and components will stay safe in teh face of voltage fluctuations. 

Types of Surge Protection Devices

Based on the points of installation and level of protection offered, SPDs are divided into various types. Understanding different types of SPDs is necessary, as it helps you make the right choice for your control panels and overall electrical systems. Here is a breakdown:

Type 1 Surge Protection Devices

1. Protect against high voltage surges, those directly from lightning strikes or high-voltage events. 
2. These SPDs are installed before the main distribution board, often at the service entrance or within the primary breaker panel. 
3. Type 1 surge protection devices are best suited for commercial buildings or industrial sites with external lightning protection systems.
4. Used in large industrial setups where direct lightning strikes pose a risk to control systems and machinery.

Type 2 Surge Protection Devices

1. Protect against residual surges that are left behind by the type 1 SPDs and surges caused by switching operations. 
2. These are installed at the main distribution panel or sub-panel and offer ongoing protection throughout the system.
3. Commonly used in residential, commercial, and solar-powered systems. 
4. Type 2 Surge Protection Devices protect control panels from internally generated surges in industrial, commercial, and residential environments.

Type 3 Surge Protection Devices

1. Protect against low-energy surges and are installed near sensitive electronic equipment. 
2. They provide localized protection for appliances, electronic devices, and other equipment and act as the final line of defense. 
3. Type 3 Surge Protection Devices are ideal for protecting individual devices and appliances.

Choosing the Right SPD for Your Needs

When it comes to choosing the right SPD for control panels, it is essential to ensure that they are protected against electrical surges. Here are a few factors and risks you must consider.

Factors to Consider

• Maximum Continuous Operating Voltage (MCOV): 

This is the maximum voltage that an SPD can handle continuously. It’s recommended to select an MCOV that has a voltage slightly above your system’s nominal voltage to ensure long-term protection. For example, if your system’s nominal voltage is 230 volts, an SPD with an MCOV of 300V will provide enough overhead to manage voltage fluctuations. 

• Voltage Protection Rating (VPR): 

This indicates the clamping voltage at which the SPD begins to divert excess voltage. When selecting an SPD, you need to be sure that the VPR corresponds to the tolerance level of your equipment, so as to avoid damage. 

• Nominal Discharge Current (In): 

This represents the current an SPD can discharge continuously without degrading. The higher the value of In the longer the lifespan of your SPD. 

• Response Time: 

SPDs for control panels should have a quick response time so they can provide instant protection as soon as a surge is detected.

Assessing Surge Risks

When selecting SPDs, consider the environment they will be used in and the potential risk factors:

• Residential: Residential areas usually need protection from internal surges caused by appliances.
• Commercial: In commercial settings, protection is required against surges from internal switching and external grid fluctuations. 
• Industrial: Industrial control panels are exposed to both internal and external surges, because of the heavy machinery used and surges caused due to lightening strikes. 

Installation and Maintenance of SPDs

Proper installation and maintenance of the SPDs are necessary to keep your electronics safe.

Installation of SPDs

• Install SPDs at the key points; remember, type 1 SPDs are installed at the service entrance, type 2 are installed at the distribution board, and type 3 are installed close to sensitive equipment. 
• Be sure that there is proper grounding so the excess surge can be dissipated easily.
• Prefer a coordinated approach, with type 1, type 2, and type 3 SPDs working together to provide protection.

Maintenance Tips

• Regularly check your SPDs for any signs of damage. 
• Replace SPDs after a significant surge event or according to the manufacturer’s recommendations. 
• Choose surges with an indicator to know their status and effectiveness.

Benefits of Using SPDs for Control Panels

Here are some of the major benefits of using control panel surge protection:

1. SPDs protect your systems and equipment against harmful high-voltage surges, which reduce the downtime and the cost of repairs. 
2. Extends the life of your electrical appliances by mitigating the risk of wear and tear from unexpected surges. 
3. Mitigates the risk of fire caused by electrical surges. 
4. Lowers the cost of maintenance and replacement. 

To Sum Up

Are surge protectors necessary? The answer is yes! Surge protectors protect your electrical applications from damage caused by unexpected voltage spikes. You can make an informed decision by understanding surge protection, its role, and its types.

Protect your valuable electronics with the best surge protection devices from Go Switchgear. Have a look at the wide range of SPDs available and choose the one that is right for your needs. 

For reliable surge protection solutions, visit Go Switchgear.

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