What is a Power Surge?

Posted on: February 7th, 2020 by admin No Comments
image of two power lines

We’ve all, at some point in our lives, experienced a power cut. They can be infrequent, or a regular occurrence, depending on where you live. That moment when a power cut hits our home we instantly recognise it. Suddenly everything goes dark, perhaps a house alarm is triggered, and we must light a candle or find a torch to switch it off, but more importantly, see. 

The TV also switches off. At this, we audibly groan as we suddenly realise we won’t find out the ending of our favourite weekly programme – will Janet catch her husband cheating? We’ll never know, unless this is a short power cut. We hope it is; we want justice for Janet, she deserves to know the truth. 

Our Wifi also goes down. This moment of realisation is filled with sinking dread – how will we fill our evening now without scrolling endlessly through social media? Our connectivity to the online world temporarily cut off. Our online presence temporarily vanished. We are present in the real world, yet in the dark in both, and it feels odd. Thoughts flicker through our head. We panic – how long will this power cut last?

We’ve all experienced this. We know the feelings well. But, have you ever wondered why and how a power cut is caused? They are caused by a significant surge in power.

What is a power surge?

A power surge occurs when there is a fast, extreme pulse, boost, or increase in electrical voltage. This has a knock-on effect and causes an increase in electrical energy, increasing the current flowing to our plugged in devices, appliances and wall outlets. 

The most common cause is due to an oversupply of electricity and voltage from our power company. This can last a few microseconds, but the voltage can reach 6,000 volts or 3,000 amps when it arrives at our home, and to our equipment.

Power surges are considered the most dangerous of all power disturbances. They can damage and fry our electrical equipment, particularly those not guarded by a surge protector. As the surge in electrical power outpaces the maximum voltage, it can cause lasting damage.

What can cause a power surge?

Power surges can be caused by a number of different things:

  • Lightning
  • Operating high power electrical devices
  • Faulty wiring
  • Problems with power lines, generators and at your power supplier

From our list, a strike of lightning is the least common cause of electrical power surges, but it is the most intense and damaging. The best protection against a lightning power strike is to unplug any electrical devices and appliances you have during a storm.

For buildings that have larger, high powered electrical devices, such as refrigerators, air conditioners or elevators, their operation can cause surges in power, particularly when switched on and off. As they require a lot of energy, this simple action can cause sudden, brief demands for power and result in severe damage.

Problems at your electrical power supplier or distribution company can range and there are many potential points for failure that could cause an uneven power flow. Unfortunately, within electrical distribution power surges are an unavoidable occurrence.

How do you know if you have a power surge?

If you suspect your home has had a power surge whilst you were away, then you can troubleshoot by checking for these 3 key indicators:

  1. Flashing electrical devices – if your devices are flashing and they don’t typically do this, there’s a high chance you’ve experienced a power surge.
  2. Plugged in equipment not working – if equipment is plugged in and does not work, there might be a chance that it’s stopped working due to a power surge.
  3. Burnt electrical smell – does the area around your devices, equipment or appliance smell burnt? This could be because of the high voltage spike caused by a power surge.

How to stop a power surge?

Whilst electrical power surges are often out of our control if they are caused by lightning, or our power company, there are a few steps we can take during a power cut. This can include reporting the issue, calling an emergency electrician, or even checking a live power cut map in your local area for London, East Anglia and South East England.

Some steps you can take to prevent a power surge include: inspecting your wiring, unplugging electronics during a storm, and using surge protectors.

Contact Us

If you need an emergency electrician and live in the London area, you can call our team on 0203 633 4536 or contact us by filling out our online enquiry form and we’ll be in touch.

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