Understanding Three Phase Circuits: Direction of Arrows

AI Thread Summary
The arrows in the figures indicate the direction of voltage induced in the windings based on current flow. For instance, if current flows from terminal n to R, the voltage VnR is considered positive in that direction. The direction of the arrows is not fixed; they can be reversed depending on the current's flow. The anti-clockwise direction of line voltages (VYR, VBY, etc.) represents the phase sequence in three-phase circuits. Understanding these directions is crucial for analyzing circuit behavior and ensuring proper functionality.
ranju
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In the given figures , what does the arrows denote , I mean what direction ??
VnR is upward in 1st fig. , VnR is towards left in 2nd fig. ( n is neutral here ) while in 3rd the line voltages are in anti-clockwise direction..!
I wanted to know the pupose of this and why these directions only??
 

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ranju said:
In the given figures , what does the arrows denote , I mean what direction ??
VnR is upward in 1st fig. , VnR is towards left in 2nd fig. ( n is neutral here ) while in 3rd the line voltages are in anti-clockwise direction..!
I wanted to know the pupose of this and why these directions only??
The arrow denotes the sign of voltage induced in the winding when current flows in that direction. For example if current flows from terminal n to R, the voltage across the winding denoted by VnR is positive.
 
This means it is not a particular rule we can take this in opposite direction too ??
And what about the anti-clockwise direction of line voltages (VYR ,, VBY..) ??
 
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