• Line Loss Pro

The Affects of Noise and Harmonics on Power Systems

Updated: Aug 14, 2019

Have you ever wondered why there are thousands of volts delivered to the spark plugs of an automobile engine, but the battery is only 12 volts?

Noise and Harmonics in a power system most often results in power loss delivered to the load (Appliances, LED Lighting, Air Conditioners, VFD’s, Motors, Computers and all Electronic Devices).

The loss of power costs money and also wastes precious resources. Many of the adverse signals that reduce power are originated in the ground and neutral lines of power systems.

Noise and Harmonics are caused by nonlinear loads. These are loads which draw short bursts of current and have resulting non proportional current to voltage ratios.

Most electronic devices used are nonlinear, meaning there are either inductive or capacitive devices within the system which react to changing frequencies (most conventional power sources) and even react to the initial startup of the application of DC power.

Have you ever wondered why there are thousands of volts delivered to the spark plugs of an automobile engine, but the battery is only 12 volts?

This high voltage is derived from opening and closing a switch at a rapid frequency while applying power to the ignition coil. Until the 1970’s that was accomplished with a mechanical switch (points) located in the distributor and was later replaced with a transistor switch.

The formula for this is expresses as:

VL = L di/dt

In lay person terms this means the voltage across the inductor basically changes with respect to time.

This phenomenon creates large voltage spikes when the switch opens in an inductive circuit, because the current cannot change instantaneously and if the current cannot change instantaneously, the voltage must increase to react to the large impedance of an open switch.

This can be understood from the basic formula of Ohm’s Law:

V = I x R

Where V = voltage, I = current and R = resistance. Equations must always balance.

The harmonics created from nonlinear loads deconstruct into a series of sinewaves, which are multiples of the primary frequency of the input waveform. Since the frequencies are out of phase with the input waveform, there is a constant addition and subtraction from the value of the primary input waveform.

This becomes numerically complex, because of the multitude of waveforms and the variance of frequencies.

The results cause motors (air conditioners, elevators, industrial motors, fans and other devices) to operate inefficiently, because of the effects of noise and phase shifting of the input supply voltage. Motors dissipate this wasted energy as heat in most cases.

Another forgotten cause of noise are the electrical lines delivering power to the load. As power lines increase in length and wrap around objects on the way to the load, these wire become inductive and create a reactive load to the source, even before arriving at the actual intended load (device).

The important concept to remember is that every location is different and it would be impossible to bundle all locations into a single solution and even after a location is outfitted with a filtering solution, its load reactive profile can change as devices are added or subtracted from the load. This is the reason that some locations will perform better than others when it comes to filtering results and that is why a seven to seven day comparison is recommended to validate filter performance.

The best candidates for savings with filtering are usually clients with heavy loads and loads that are highly inductive. This includes most factories, office buildings, computer and networking companies, hospitals, malls, locations that use large central air conditioners, escalators or elevators and any location that has electric motors and equipment, including pool and water feature motors. Although filtering should not be limited to these locations, these types of locations should produce the best savings results.

Removing noise from an electrical system can reduce power bills, but can also extend the life of motors and other electrical devices. Many companies filter computer systems for this same reason and because failure and poor performance is easily identifiable in systems that businesses heavily depend on for daily operations.

Line Loss Pro has developed a patent pending, UL Listed device that can help cancel noise and harmonics and create a more efficient delivery of power to load devices. This device’s purpose is consistent with the preceding discussion.

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