Application Guide - NP900 Series
307 (504
)
A996A
3.5
T
RANSFORMER PROTECTION MODULE
3.5.1
T
RANSFORMER STATUS MONITORING FUNCTIONS
Transformer status monitoring function (TRF) is designed to be the common place for set
up all necessary transformer data and to select the used transformer protection functions.
Settings related to the protection functions can be edited also inside of each related
function and after changed they will be updated into TRF function also. TRF function
calculates many transformer related properties which are used in functions for protecting
and monitoring the transformer. Basically for standard transformer only name plate data is
needed as well as CT scalings to get the relay scale automatically all measurement
signals to the transformer. For special transformers manual set can be applied to cover
rarely met transformers properties. In addition to transformer data and measurement
scaling settings TRF function counts transformer cumulative overloading and high
overcurrent time.
From TRF function can be output light/no load, HV side inrush, LV side inrush, normal
load, overloading and heavy overloading signals to be used in indication or in application
logics. From these signals TRF also generates events if so wanted.
Figure 3.5.1-149 Simplified function block diagram of the TRF function.
