9.3
Setting group N
9.3.1
Overview
There are some default setting groups. Under general settings, parameters in these
groups can be changed to suit the needs of an application. The default settings have
been chosen according to established practice in the industry but will usually
require a certain amount of adjustment to suit the requirements of individual
applications.
9.3.2
Differential protection
9.3.2.1
Overview
The settings available for differential protection in Setting group N are not the
same as those under General settings. The main difference is that settings in the
Setting group N category can be changed on the fly without the IED requiring a
restart. A dialog box appears when attempting to make changes to setting group N.
Choose OK to proceed, or cancel to abort.
9.3.2.2
Transformer differential protection, two winding T2WPDIF
Main menu/Settings/Setting group N/Differential protection/
TransformerDiff2Wind(PDIF,87T)/T2WPDIF:x
There are a number of possible settings for T2WPDIF . These are used to adjust the
limits on the curve determining the operation of the function. The slope of the
curve in section two and section three of the curve can be adjusted and the end
points of section one and section two can be set along the Ibias axis. The slope of
the curve in sections two and three can also be adjusted. The unrestrained limit for
the operation of the protection can be set as a multiple of rated current for winding
one. The cross blocking function that enables a blocking condition on one phase to
prevent a trip even if a trip signal is generated by another phase, can be set on or off.
9.3.2.3
Transformer differential protection, three winding T3WPDIF
Main menu/Settings/Setting group N/Differential protection/
TransformerDiff3Wind(PDIF,87T)/T3WPDIF:x
Displays available instances of T3WPDIF with a number of settings each. The
settings for this function are identical to
"Transformer differential protection, two
9.3.2.4
Restricted earth fault protection REFPDIF
Main menu/Settings/Setting group N/Differential protection/
LowImpREF(PDIF,87N))/REFPDIF:x
Section 9
1MRK504114-UEN E
Read and change settings
56
Operator's manual
