How to Protect Electronics from Surges and other Power Quality Issues

protect electronics from power surges

There are different ways to protect electronics from voltage surges and fluctuations. The available technologies have components that regulate the incoming supply, hence prevent excess voltage from reaching the equipment. When a problem occurs in the mains, the protection system can cut off the power, or remove or divert the excess voltage to the ground. This operation depends on the design of the protection system, the magnitude, and nature of the fault.

The simplest way to protect electronics from voltage spikes is using a surge suppressor which can be in the form of a plugin device or a multi-outlet extension cord.  Other more effective means include using a whole house surge protector for the entire electrical system, or an uninterruptible power supply (UPS) for both protection and power backup.

Causes and effects of power surges and fluctuations

Electrical surges in the system may occur due to a variety of reasons. The fluctuation can occur from external factors such as lightning or trees touching and grounding some parts of the transmission systems. They can also arise from  internal causes such as faulty wiring or excess current drawn by motor starting. This leads to problems such as;

  • Overvoltage
  • Short circuits
  • Low voltage
  • Power outage

The voltage fluctuations in the system leads to  unstable power that can damage the equipment or degrade the components, hence reducing its performance and service life of the equipment. Problems may also occur when power resumes almost immediately after an outage.

Without adequate protection, the excess voltage in the electrical surge will stress the components by passing current or dropping voltage beyond the safe limits. This causes overheating and eventual breakdown or damage of the component. Such faults will render the equipment completely unusable or expensive to repair.

While it is almost impossible to eliminate some of the electrical problems in the supply lines, there are several things that you can do to protect electronics. This includes using the appropriate devices to monitor the incoming electricity and then respond appropriately.

Ways to protect electronics at home

effects of power surges and fluctuationsThe method to protect electronics depends on the type and magnitude of faults in the electrical system as well as the budget. Common and effective methods or practices include using a protective device between the equipment and the supply.

Typical devices include the surge protectors, automatic voltage regulators, UPSs, circuit breakers, fuses, etc. However, you must ensure that the wiring and grounding are installed correctly so as to effectively protect electronics hardware and software.

The following are some practical methods of ensuring that bad power does not reach the equipment.

Typical protective measures include;

  • Use a protection system or devices to protect the electronics equipment. The UPS provides additional functionalities such as maintaining the voltage within certain safe limits regardless of the supply level. In addition, it provides backup power in the event of a power failure hence giving the user enough time to safely shutdown the equipment such as computer and prevent software failures.
  • Use dedicated circuits for the delicate and sensitive equipment such as computers and electronics. Avoid connecting these with motors, air conditioners, and other heavy equipment, etc.
  • Limit the number of equipment per a single electrical outlet, if possible try to closely match the appliances to minimize interference.
  • If experiencing frequent fluctuations or spikes due to lightning or a storm, the surge suppressors may not be enough and it is advisable to completely unplug the equipment until the power stabilizes.

How to protect electronics using surge protectors

The surge suppressors do not arrest the surges; instead, they divert the energy to the ground. A typical point-of-use surge protection device looks like a standard plug, however, it has additional components to monitor the supply and respond in good time to protect electronics.

Other than the plug-in devices or extension cords, you can install electrical receptacles with inbuilt surge protection. These are usually suitable for locations where there is no room or provision for plugging in an external surge protector such as the case of a countertop microwave oven.

Another alternative technique is to install a whole house or service entrance surge protection system at the electrical panel. This has the ability to protect electronics and all appliances in the home while eliminating the need for the individual suppressor for each appliance.

A two-tier surge suppressor approach to protect electronics

Users can either choose the point-of-use or the service entrance surge protection method. Each method can be used individually or in combination with the other, depending on the desired level of protection and budget.

Such an arrangement protects electronics, motors, lights, hard wired appliances and any other load in the commercial or residential electrical system. If there is a large spike such as a lightning strike, the service entrance surge suppressor reduces the voltage before it reaches the point-of-use protector. The point-of-use plug-in suppressor will also protect electronics against internal problems.

Considerations when selecting a protection method

Speed of operation

power surges electronics protectionA protection system that responds quickly to excess voltage or current situations greatly minimizes the risk of damaging the electronics. As such, it is important to pay attention to the response time for the system you intend to use to protect electronics and other appliances.

Range of operation

Choose a protection system with many features and a wide range over which the device or system prevents bad power. This will protect electronics by preventing  the excess or unstable voltage from reaching the appliance.


There are both solid state and electromechanical surge protectors. The mechanical components may have some delays responding to surges and therefore not very effective in sensitive applications. Most of the modern suppressors are solid state and very fast. These have less mechanical problems and are easy and cheap to maintain.

Surge suppression

The suppressors differ in design and capabilities, typical devices reduce the surges of about 6000V to a harmless level of 600, 400, or 330V. Any device with the ability to reduce spikes to about 330 is the best since the load will experience less stress. However, the majority of the devices do not suppress below 600v.

Internal fuse or blowout mechanism

If the surge persists for a longer time than the suppressor can withstand or handle, the fuse opens to prevent the excess voltage from reaching the equipment. When the surge is very high, the protection device destroys itself to prevent any electricity going to the appliance.

Type of load

Some electronic equipment such as medical instruments and precision measuring instruments have very sensitive circuits that can go bad due to fluctuations in the power supply. For this reason, using a surge suppressor may not be enough because the equipment must shut down in an orderly manner. A sudden power outage have the potential to damage the components or software in the machine.

In such an application, an uninterruptible power supply (UPS) is  used. Most models have an integrated surge suppressors and automatic voltage controls to prevent overvoltage conditions. The UPS provides a backup capability to supply power when there is an outage.


The aim of any protective device is to ensure that the amount of electricity to the equipment is within its safe limits. The devices act as gatekeepers to protect electronics from high inrush currents, over-voltages or other electrical faults that can damage the equipment.

The protection system monitors the supply voltage in the circuit and either disconnects the power to the equipment.  It can also suppress the excess voltage. A UPS has additional functionalities such as regulating high or low mains supply to suit the recommended voltage level, hence providing a better means to protect electronics.