Figure. 5.3.7. - 62. An example of measured neutral voltage.
The setting group selection controls the operating characteristics of the function during normal
operation, i.e. the user can change parameters while the station is running.
The output of the function is the ALARM signal. The setting parameters are static inputs for the
function which can only be changed by the user in the setup phase of the function. The neutral
overvoltage function uses a total of eight (8) separate setting groups which can be selected from one
common source.
The operational logic consists of the following:
input magnitude selection
input magnitude processing
threshold comparator
output processing.
The inputs for the function are the following:
operating mode selections
setting parameters
digital inputs and logic signals
measured and pre-processed voltage magnitudes.
The function's output ALARM signal can be used for direct I/O controlling and user logic programming.
The function registers its operation into the last twelve (12) time-stamped registers and also generates
general time-stamped ON/OFF events to the common event buffer from the output signal. The time
stamp resolution is 1 ms. The function also provides a resettable cumulative counter for ALARM
events.
Measured input
The function block uses analog voltage measurement values and always uses fundamental frequency
RMS values.
Table. 5.3.7. - 69. Measurement inputs of the U0> function.
Signal
Description
Time base
U0RMS
Fundamental RMS measurement of voltage U
0
/V
5 ms
AQ-E215
Instruction manual
Version: 2.01
89
© Arcteq Relays Ltd
