Functionality; Operation Principle - ABB RELION 620 Series Technical Manual

Section 4
Protection functions
4.4.2.3
4.4.2.4
344

Functionality

Ground directional power protection 32N is used to detect negative or residual power
direction. The output of the function is used for blocking or releasing other functions in
protection scheme.
In negative-sequence voltage selection, if the angle difference between negative-
sequence voltage and negative-sequence current is in a predefined direction (either in
forward or reverse direction), 32N gives a release signal after a definite time delay.
In residual voltage selection, if the angle difference between residual voltage and residual
current is in a predefined direction (either in forward or reverse direction), 32N gives
release signal after a definite time delay.
This function contains a blocking functionality which blocks the function output and
resets Timer.
32N executes on the direction of either negative-sequence or zero-
sequence power and not the value. 32N is generally used for directional
controls.

Operation principle

The function can be enabled and disabled with the Operation setting. The corresponding
parameter values are "Enable" and "Disable".
The operation of directional negative/zero sequence power protection (32N) can be
described with a module diagram. All the modules in the diagram are explained in the next
sections.
1MAC504801-IB E
620 series ANSI
Technical Manual