# Negative Sequence Voltage Calculator

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The positive sequence is made up of three-phase voltage & current phasors that are balanced and rotate in an ABC rotation; these phasors are exactly 120 degrees apart from one another.

The negative sequence is made up of 3-phase voltage & current phasors that are balanced and rotate counterclockwise in ACB rotation. These phasors are exactly 1200 apart from one another.

A balanced three-phase voltage and current is what makes up zero sequence. The phasors of zero sequence all have the same phase angles & rotate together in a counterclockwise direction.

The Negative Sequence Voltage (LLF) formula is defined as consisting of balanced three-phase voltage and current phasors that are exactly 120 degrees apart and rotate counterclockwise in ACB rotation.

The sign V2 denotes negative sequence voltage.

The Negative Sequence Voltage (LLF) calculator calculates Negative Sequence Voltage as

Negative Sequence Voltage = Positive Sequence Voltage – (Fault Impedance X Positive Sequence Current)

V2 = V1 – (Zf X I1)

Where,

V2 – Negative Sequence Voltage (Measured in Volt) represents balanced three-phase voltage & current phasors that are 120° apart revolving counterclockwise in ACB rotation.

V1 – Positive Sequence Voltage (Measured in Volt) – Balanced three-phase voltage & current phasors are 120° apart and rotate counterclockwise in ABC.

Zf – Fault impedance (measured in Ohm) – In case of a fault, fault impedance (measured in Ω) is used to determine fault current.

I1 – Positive Sequence Current (Measured in Ampere) – Balanced three-phase voltage & current phasors are 120° apart and rotate counterclockwise in ABC.

To utilize this online calculator for Negative Sequence Voltage (LLF),

enter

1. Positive Sequence Voltage (V1),
2. Fault Impedance (Zf), and
3. Positive Sequence Current (I1) and
4. Output Value is derived.

Here is how the Negative Sequence Voltage (LLF) calculation might be explained using the provided input values.