 ## What happens if load is unbalanced?

The unequal distribution of loads between the three phases of the system cause the flow of unbalanced currents in the system, that produce unbalanced voltage drops on the electric lines.

This increase in neutral current which cause line losses..

## What is a balanced 3 phase system?

The sum of each of the voltages (and currents) at the star point is always zero. In a balanced system, the neutral current and neutral power is zero. You can think of a balanced three-phase system as three single-phase systems connected to a neutral line.

## How is load imbalance calculated?

There are three steps in the calculation:Determine the voltage or current average.Calculate the largest voltage or current deviation.Divide the maximum deviation by the average voltage or current and multiply by 100 % unbalance = (Max deviation from average V or I/average V or I) x 100.

## How do you reduce unbalanced voltage?

Redistributing and reconnecting single-phase loads can reduce voltage unbalance caused by excessively unequal load distribution among phases. The most prevalent culprits among heavy, single-phase loads are lighting equipment and occasionally welders.

## What is a phase in electricity?

In electricity, the phase refers to the distribution of a load. … Typically, there is one power wire—the phase wire—and one neutral wire, with current flowing between the power wire (through the load) and the neutral wire.

## What is meant by unbalanced load?

An unbalanced 3 phase load is one in which the load is not equally distributed over all the three phases. To obtain the equivalent 3 phase rating the highest single phase loading must be multiplied by 3. An unbalanced load give rise to unequal phase to phase and phase to neutral voltages.

Unbalanced voltages usually occur because of variations in the load. When the load on one or more of the phases is different than the other(s), unbalanced voltages will appear. This can be due to different impedances, or type and value of loading on each phase.

## What happens if loads are unbalanced in 3 phases?

An unbalanced three-phase system can cause three-phase motors and other three-phase loads to experience poor performance or premature failure because of the following: Mechanical stresses in motors due to lower than normal torque output. Higher than normal current in motors and three-phase rectifiers.

## How do you fix phase imbalance?

A building monitoring system protects against premature equipment failure by monitoring for several common fault conditions including phase unbalance. Notifying operators to turn off equipment or motors in real-time has been proven to help correct phase imbalances before damage occurs.

## Why neutral current is high?

High neutral currents in buildings usually result from two situations. The first, and most common, is one where there are simply heavily unbalanced loads. … In today’s environment, it is becoming increasingly likely that high neutral currents result from some combination of the two.

## How do you calculate the power of an unbalanced load?

kbarbthe line to neutral (phase) voltage VLN = 208/√3 = 120 V.phase 1 apparent power = 42 x 120 = 5040 VA = 5.04 kVA.phase 2 apparent power = 84 x 120 = 10080 VA = 10.08 kVA.phase 3 apparent power = 80 x 120 = 9600 VA = 9.6 kVA.Total three phase power = 5.04 + 10.08 + 9.6 = 24.72 kVA.