Table. 5.4.14. - 132. Register content.
Date & Time
Event code
df/dt Pretrig
(Hz/s)
f Pretrig (Hz)
df/dt Fault
(Hz/s)
f Fault
(Hz)
Setting group
in use
dd.mm.yyyy
hh:mm:ss.mss
6592-6639
Descr.
Start –20ms
averages
Start –20ms
averages
Fault df/dt
Fault
frequency
1-8
5.4.15. Power protection (32)
PQS power protection function is for instant- and time delayed active, reactive or apparent three phase
over or under power protection. Operation mode is selected by user with parameter settings.
Figure. 5.4.15. - 66. Pick-up areas of the different modes in PQS power protection function displayed in a PQ diagram.
Outputs of the function are Start Trip and Blocked signals. Setting parameters are static inputs for the
function which are changed only by user input in the setup phase of the function. PQS power
protection function utilizes total of eight separate setting groups which can be selected from one
common source.
The function can operate on instant or time delayed mode.
The operational logic consists of input magnitude processing, threshold comparator, two block signal
check, time delay characteristics and output processing.
Inputs for the function are the operating mode selections, setting parameters and measured and pre-
processed power magnitudes and binary input signals. Function outputs START, TRIP and BLOCKED
signals which can be used for direct IO controlling and also for user logic programming. The function
registers its operation into 12 last time-stamped registers and also generates general time stamped
ON/OFF events to the common event buffer from each of the three output signal. In instant operating
mode the function outputs START and TRIP events simultaneously with equivalent time stamp. Time
stamp resolution is 1ms. Function provides also cumulative counters for START, TRIP and BLOCKED
events.
AQ-T257
Instruction manual
Version: 2.00
© Arcteq Relays Ltd
128