Distortion in the voltage or current wave of electrical devices causes harmonics. Distortion means that the distribution of electrical energy is problematic and the quality of power is low. It can have different effects on electric equipment, damaging them in various ways. Some of the problems caused by harmonics are capacitor failure, circuit breakers tripping, flickering of fluorescent lights and motor failure. Electrical technology has improved, offering us smaller and lighter electrical components that need clean electrical power to work properly. This means that modern equipment requires undistorted voltage and is highly sensitive to power distortions. Total harmonic distortion (THD) is a difference in harmonic frequencies. The amplifier compares the output signal with the input signal and this way measures this difference.
Switch Mode Power
Switch mode power supplies (SMPS) are one of the causes of harmonics. TVs, radios, fax machines, stereos, dimmers, computers and laser printers usually use SMPS equipment. SMPS converts AC voltage to low voltage DC for electronic devices, which are also referred to as non-linear loads. These non-linear loads can cause distortion in the electrical current and voltage, which leads to harmonics.
Dedicated Circuit
A dedicated circuit consists of three conductors and is sometimes incorrectly referred to as isolated circuit. If the SMPS devices and other utilities are on the same circuit, these utilities can also suffer serious damage caused by distortion. Electrical harmonics will lead to malfunction of all devices.
Inadequate Grounding
Inadequate grounding can cause serious damage to other devices if it comes to harmonics. If SMPS devices share a ground wire with other electrics, distortion will have affect on both. A solution is to install separate ground on outlets that power non-linear loads, or in using an over-sized "neutral." This can prevent damage caused by overheating.
Treating Harmonics
Harmonics can cause irreparable damage to your facility, so to prevent this, you have to treat it. You can choose filtering or cancellation. A harmonic filter is designed to filter a predetermined harmonic frequency range, which accounts for only one harmonic frequency. The other option is harmonics cancellation, where you use harmonic canceling transformers to remove high neutral current and harmonics from the third through the 21st. You can use these transformers to treat existing harmonics and to prevent future ones from happening.
Tags: non-linear loads, damage caused, harmonic frequency, means that, serious damage, SMPS devices