How Surge Protectors Work 2020

When for a billionth of a second a sudden rise of voltages pasts 120 volts in electrical appliances, a what is called a power surge occurs. Power surges, or transient voltage, can quickly cause major damage to electrical appliances and devices if they are high enough. This is because there is too much electrical pressure within the wires, therefore, the wires heat up immensely and “bursts”. The electrical device or appliance may not stop working, however, components within will be strained and damaged, worsening over time.

The main function of a surge protector is to prevent the high voltages from flowing through the wires of electrical devices and causing destruction. To do this, a Metal Oxide Varistor (MOV) is placed within the power surge protector and acts to resist/divert the high voltage currents from damaging the appliance. The Metal Oxide Varistor connects to the hot power line and the grounding line.

A MOV contains three parts in its body, including a piece of metal oxide material. This is connected to both the power and the grounding line through two semiconductors. The variable resistance of these two semidictors depend on voltage. This means that determining on the level of voltage present, the MOV will act accordingly. If the voltage remains beneath a certain threshold, or being low, a very high resistance of electrons is created by the semiconductors. The opposite occurs when the voltage goes beyond that specific level and when it is correct the MOV does nothing.

When the voltage is too high and can lead to permanent damage, the MOV acts to divert the electric current into itself and the ground. This means that the MOV’s resistance increases as the voltage in the hot line goes back to normal. The standard electrical current is still able to continue power the electronic device or machine while this whole process occurs because the MOV simply veers the surge current away.

Due to modern electrical devices and appliances being smaller, sophisticated and, therefore, delicate when compared to older machines. They are more sensitive and prone to be more damaged with high voltage surges. It still depends though on the appliance if it truly needs a surge protector:

Within Australia, there are no compulsory laws or standards stating that you have to or which surge protectors to use. There are guidelines and advice provided by Electrical Comms Data (ECD).

Some examples of which surge protectors to use are:

• Basic Power Strip – used at a basic level with five or six outlets. Providing basic protection as they are a basic extension.
• Better Power Strip – these are a little more expensive, however, offer more protection. Additionally, they have other features, as well as greater ratings.
• Surge Stations – larger than the previous, these ones usually are applied for computers and other appliances. They have a more effective and greater voltage protection. Moreover, most contain an input to apply phone lines to, protecting modems, and also may have built-in circuit breakers. These are more expensive, yet, more safe and protecting.