What Is An Electrical Spike (Surge)?

 

An electrical spike is a temporary, very short (less than a second), increase in the electrical supply voltage (or current or both). Another name for an electrical spike is an electrical surge.

 

 

 

Why Is The Increase In Electrical Supply Called A Spike?

 

Short-term increases in the electrical supply voltage, or current or both, are called ‘spikes’ because if you look at the electrical supply with some types test equipment, for instance an oscilloscope, the rise in voltage (or current or both) looks like a spike on the oscilloscope display.

 

The image on the left is an oscilloscope display.

 

The oscilloscope display shows the electrical supply voltage level (red line).

 

The normal UK electrical supply voltage is 240 volts.

 

The red line on the display shows that the electrical supply voltage is 240 volts most of the time.

 

An electrical surge causes the supply voltage to increase from 240 volts to 600 volts for a short period of time.

 

 

 

Electrical Spike

The short-term increase in voltage causes the oscilloscope display (red line) to increase; the supply voltage soon goes back to 240 volts and the red line goes back down. 

 

The red line that represents the supply voltage value looks like a spike, hence the name ’electrical spike.

 

 

 

What Problems Does An Electrical Spike (Surge) Cause?

 

RCD Problems

 

Electrical spikes often cause RCDs to trip.

 

The effect of an RCD tripping can be no electrical power to a house or workplace or part of a house or workplace; reset the RCD to restore power.

 

RCDs are safety switches that prevent high currents and voltages flowing in an electrical circuit.

 

About RCDs

 

Find, reset and investigate a tripping RCD

 

How to reset and RCD

 

RCD Links

 

 

Damage To Electrical Appliances

 

The surge in voltage, or current or both, can damage electrical appliances, for instance PCs, televisions and sound systems.  The electrical surge can damage any electrical appliance that is plugged in.

 

An electrical spike can also damage internet routers and modems if the electrical spike ‘gets into’ the telephone circuit.

 

More often than not the only solution is to replace the electrical appliance.

 

 

 

How To Protect Against Electrical Spikes

 

It is possible to prevent, or lessen, the damage from an electrical spike.

 

Putting electrical spike protection into an electrical circuit is called ‘surge protection’.

 

Surge protection can be as simple as putting an adaptor into an electrical socket; electrical surge protection can also be complex and expensive.

 

About Electrical Surge Protection

 

 

 

Links

 

Electrical Surge Protection

 

Domestic Electrical Sockets

 

Home Lighting Troubleshooting Tips

 

Links To Domestic Electrical Advice

 

Resetting RCDs

 

What Causes An RCD To Trip

 

 

This web page describes:

 

· What an electrical spike is.

 

· Why it is called an electrical spike.

 

· What problems an electrical spike causes.

 

· How to protect against electrical spikes.

 

 

Electrical Spikes And Surges

Home > Small Business Advice > Electrical Surge Protection > Electrical Spikes And Surges

Judge Electrical Logo

About Us       Accreditations       Contact Us       Services Offered       Prices       Where We Are       Search This Site