Commercial Surge Protection – What is it?, types, how it’s used?

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Commercial Surge Protection

Electricity is such as huge part of our lives that it is often very easy to take it for granted. Every time you turn on a light, plug in your computer, or complete other tasks, you just assume that the power will always be there.

It is when something goes wrong, like a power outage or a power surge, that you realise how important it is and how crucial its maintenance and upkeep are.

A power outage is only a temporary interruption, although it can be disruptive for your business, whereas a power surge is a more pressing issue that can be more destructive and cause harm to your electric appliances and systems.

Luckily, there is a solution for power surges in the form of surge protection devices that can be used in commercial properties such as offices, banks, supermarkets, shopping centres, and many more places.

Read on to find out more about commercial surge protection, what it is, how it is used, the different types of surge protection devices, and much more:


A power surge refers to a spike in the power supply coming into your property that results in an increase in the voltage above the designated flow of electricity.

It can be caused by several reasons that include:

Damaged or exposed wiring

Damaged and exposed wiring is not only a safety hazard but can also result in frequent power surges. At times, they can occur several times during the day, putting your electronic devices, appliances, outlets, and switches at risk.

Internal power surges may often go unnoticed, but there are a few signs to look for that include warm outlets and a burning smell.

As soon as you notice any of these, take the necessary measures to fix them ASAP as ignoring them for too long may result in damages in the form of short-circuiting and safety risks in the form of shocks, burns, and fires.


Lightning can have devastating effects when it strikes, causing power outages, blackouts, and even fires, and a power surge caused by lightning can ruin electronics and appliances on your property.

The damage is caused when the surge is so high that appliances like computers, printers, and other machines plugged into the main supply cannot withstand it and suffer the same consequences.

Circuits overloading

Offices and other commercial buildings often face short-term power outages when an electrical overload causes the circuit to trip momentarily.

This is because some systems and appliances consume more electricity, for instance, commercial buildings with multiple elevators and air-conditioners. The sudden spike in electricity use causes a surge and damages valuable electrical equipment.

Momentary power outages

As discussed above, momentary outages can also result in electrical surges which, when occurring too frequently, affect the electrical flow and can either trip the circuit or cause a sudden spike in the voltage.

Either way, it can cause damage to electrical equipment and machinery and these outages are usually a result of external factors rather than internal ones.

External factors

External factors such as weather conditions, trees, and animals can cause electrical surges. Weather conditions, such as extreme temperatures, snowstorms, and thunderstorms can result in power surges, and so can tree limbs.

Tree branches may sometimes touch or fall onto the power lines, which is why it is best to trim them. In case a tree falls on a power line, do not attempt to remove it yourself and call a professional service instead.

Animals can also be a cause of power surges, such as when wild animals such as birds and squirrels make their way into the transformers and nibble at the cable. This can cause the wiring inside to get exposed which may result in short-circuits and fires.


Regardless of where a power surge originates from or what causes it, it can spell disaster for your commercial premises and may result in huge losses.

Every business is at risk. Some may be more at risk than others depending on the type of equipment they use and the health of their electrical system, but they all need to take the required preventive measures against power surges.

Most businesses these days rely on modern electronics and equipment, all of which can be weakened or damaged by power surges.

Commercial properties, particularly at risk, include those that use motors and other high voltage machinery, healthcare facilities with life support systems, and businesses dependent on computers, printers, and other electronic equipment.

Equipment that is most vulnerable includes:

  • Computers, printers, fax machines, and other electronic equipment
  • Telecommunications equipment
  • Manufacturing machinery
  • Elevators and escalators
  • Security systems and fire alarms
  • Retail POS systems


Every power surge isn’t as detrimental to your electric system and electronics’ health and voltage may fluctuate daily in most commercial properties.

Basic tasks such as turning on electrical equipment, motors, and other equipment can all result in brief power spikes. While individually they may not be as significant, they have a cumulative effect over time that can cause your electrical equipment to weaken and eventually get damaged.

Therefore, even though a power surge may last only for 1 to 2 milliseconds, the resulting problems may be serious and affect your business and its operations for a long time.

A typical surge protection device passes the electrical current along the outlets to a number of devices plugged into them. In case the incoming voltage rises above the acceptable level, it diverts the extra electricity into the grounding wire of the outlets.

Grounding wires run parallel to the hot and neutral wires and provide a pathway for the electrical current to flow in case there is a breakdown in the two wires that normally carry the current.

There are different surge protection devices based on their application and use. Commercial surge protection devices are suitable for offices and other commercial applications and are typically installed in building management systems which include systems and equipment such as computers, security systems, data centres, lifts, and various other electronic and control systems.

Here are all the reasons why investing in commercial surge protectors is a good idea:

Surge protectors prevent damage to your equipment and facility

One of the most important reasons that surge protectors are so important for commercial properties (and residential and industrial) is in their name. They protect against power surges and prevent your electrical equipment, machinery, and appliances from getting damaged because of them.

Surge protectors prevent system issues

A business environment is usually home to high levels of electrical usage and consumption. However, if your property doesn’t have a proper and regulated flow of electricity, you can expect fuses to blow up and circuits to malfunction.

Surge protectors help business operations run smoothly

Downtime for business can be detrimental and may result in serious losses in terms of time, money, and resources. If caused due to electrical issues, a surge protector will make sure the electricity is running smoothly for your day-to-day operations so that you can focus on work instead of embarrassing electrical issues.

Surge protectors protect business equipment

Most businesses rely on electrical equipment for their day-to-day operations. By using a commercial surge protector, you will be protecting valuable equipment such as computers, monitors, security systems, and manufacturing equipment against power surges and spikes.


The current wiring regulations BS 7671:2018 apply to all kinds of properties including domestic, commercial, and industrial, and state that, unless a risk assessment is carried out, protection must be provided against transient overvoltage which could lead to:

  • Serious injuries or loss of human life,
  • Interruption of public services or damage to cultural heritage,
  • Interruption of commercial or industrial activity,
  • A large number of co-located individuals being affected.

Since surges can happen at any time, it is best to make use of surge protection devices to keep your electronic installations and appliances safe from damages.

You may not need surge protection for everything, such as your desk lamps, but you will need it for electronic devices and appliances with delicate microprocessors such as your computers, laptops, and printers. You must always plug them into a surge protector instead of directly into the wall socket.

As a rule of thumb, if it is electric and expensive, you must protect it with a surge protector. Keep in mind, though, that power surges won’t necessarily destroy your electronic equipment instantly. More plausibly, it will be multiple surges over time that will cause cumulative damage.


For ultimate safeguarding against power surges and irregularities, you need to install surge protection devices. The three main types include:

Type 1 surge protector

Type 1 surge protectors act as an intermediary between the electrical grid and the consumer unit or distribution panel of your property.

They help filter the power entering the premises and make sure that transients occurring from external factors are mitigated before they enter your electric system.

They are often high-capacity and made to withstand a partial lightning current with a waveform of 10/350µs.

Type 2 surge protectors

Type 2 surge protectors are used to reduce power surges caused both internally and externally and are installed alongside the main consumer unit.

Useful in both commercial and residential properties, they are intended to protect sensitive equipment and, compared to type 3 surge protectors, are far more capable of minimising small and large surges.

Type 3 surge protectors

Type 3 surge protectors are one of the most commonly seen surge protectors that can redirect and protect against medium surges.

They provide local protection for sensitive equipment and are much smaller scale as compared to the other types. Also, since they have a relatively low charge capacity, they must only be installed as a supplement to type 2 surge protectors.


Surge protectors come in all types, shapes, sizes, and price ranges, and it can be confusing to choose the right one for your needs. Here are a few things to consider when making the decision:

  • The exposure of your property to lightning transients
  • The sensitivity of your electronic equipment requiring protection
  • The location of the equipment
  • The exposure level of the installation

There are certain features that all good surge protectors share and you must keep them in mind when getting one. They include:

Joule Rating

Joules are the standard unit for measuring the energy released over a period of time. A surge protector’s joule rating indicates the maximum amount of energy the device can absorb.

If the power surge exceeds the limit, it renders the surge protector useless. The higher the joule rating, the more power it can absorb. Therefore, the more joules, the better.

Keeping that in mind, you need to decide how much surge protection you need based on certain things such as the value of the equipment being protected against power surges and the number of devices that require protection.

Usually, 1000 joules will be enough for smaller electronics whereas 2000 to 3000 joules should be sufficient for appliances such as computers, printers, and copiers.

Indicator Lights

Depending on how hard they work, even when a surge protector diverts excess voltage, it can suffer damages while doing so and has a limited lifespan.

That being said, an indicator light is an extremely useful feature since it tells you whether or not the surge protector is working fine. If the indicator light is not working, it probably means that the surge protector isn’t working either and it is time to either get it repaired or buy a new one.

Clamping Voltage

The clamping voltage refers to the measurement that alerts the surge protector to start redirecting the excess voltage away from your property and the plugged-in devices.

A surge protector with a lower clamping voltage will trigger earlier and protect your devices much quicker.

Response Time

The response time of the surge protector refers to the time it takes for the device to detect a power surge. A lower response time equals a faster response and a higher response time equals a slower one.

A quick response time reduces the time your plugged-in devices and appliances are exposed to the surge, providing much better protection. Ideally, you should opt for a surge protector with a response time of 1 nanosecond or less.

UL Rating

All good surge protectors come with a UL rating, which is a rating put out by the independent Underwriters Laboratories, that tests the safety of the devices.

If the surge protector doesn’t have a UL rating, don’t bother buying it. In addition to a UL rating, make sure it is a transient voltage surge suppressor since many UL-rated power strips don’t offer surge protection.


Other than installing commercial surge protection devices to protect your property and its electrical systems and appliances from power surges, there are a few other steps you can take to minimise the issue.

The first step is to make it a habit to always unplug devices when they are not in use. Even when switched off, a plugged-in device can be affected by an electrical surge.

Unplugging devices that aren’t running 24/7 will help prevent possible damage and save business owners from costly repairs and replacements.

The second step is regular maintenance. One of the biggest causes of power surges is inadequate and faulty wiring and installation. There are several reasons to get maintenance checks and inspections for your business’s wiring and electric systems, one of them being fixing minor issues and preventing power surges.

It is a requirement under The Electricity of Work Act 1989 that as a business or commercial space you make sure the electrical installations are deemed safe for use by your employees and the public. This is done by carrying out an Electrical Installation Condition Report (EICR) at regular intervals depending on use, which can range from 3 to 5 years.


We have been providing electrical services to residential, commercial, and industrial properties for over 40 years and are specialists in all aspects of electrical installations, maintenance, and testing.

We have experienced, fully qualified, NICEIC registered electrical engineers on hand to deliver a professional and high-quality service following the current wiring regulations.

If you have unplanned issues within your home or business, we can provide a call out service to rectify and solve any problems – ranging from circuits tripping, loss of power, broken items that need repairing, distribution board and consumer unit upgrades, to surge protection installation services, and much more.

Our team can generate a Visual Inspection Report (VIR) to identify anything visual that does not comply with the standards or looks unsafe, as well as a full Electrical Installation Condition Report (EICR) where we identify and test each circuit to make sure they are not deteriorating and are safe for use within the current standards and regulations set by the BS 7671.

We also provide PAT testing of appliances to make sure that any items such as kettles, computers, and microwaves are safe for use in the home and workplace.

Contact us here or call us on 0800 612 3001 to talk to our certified team of electricians to protect your electronic systems and equipment from power surges right away!

Photo by Linh Ha on Unsplash