input magnitude selection
input magnitude processing
saturation check
threshold comparator
output processing.
The basic design of the supervision function is the three-pole operation.
The inputs for the function are the following:
operating mode selections
setting parameters
digital inputs and logic signals
measured and pre-processed current magnitudes.
The function's output ALARM signal can be used for direct I/O controlling and user logic programming.
The function 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 current measurement values and always uses peak-to-peak
measurement from samples. The monitored magnitude is equal to fundamental frequency RMS values.
The operating decisions are based on phase current magnitudes which the function constantly
measures.
Table. 5.3.1. - 44. Measurement inputs of the I> function.
Signal
Description
Time base
IL1RMS
Fundamental RMS measurement of phase L1 (A) current
5 ms
IL2RMS
Fundamental RMS measurement of phase L2 (B) current
5 ms
IL3RMS
Fundamental RMS measurement of phase L3 (C) current
5 ms
Pick-up
The
I
set
setting parameter controls the the pick-up of the I> function. This de nes the maximum allowed
measured current before action from the function. The function constantly calculates the ratio
between the
I
set
and the measured magnitude (
I
m
) for each of the three phases. The reset ratio of 97
% is built into the function and is always relative to the
I
set
value. The setting value is common for all
measured phases. When the
I
m
exceeds the
I
set
value (in single, dual or all phases) it triggers the pick-
up operation of the function.
Table. 5.3.1. - 45. Pick-up setting.
Name
Description
Range
Step
Default
I
set
Pick-up setting
0.10…40.00 × I
n
0.01 × I
n
1.20 × I
n
The pick-up activation of the function is not directly equal to the START signal generation of the
function. The START signal is allowed if the blocking condition is not active.
AQ-E215
Instruction manual
Version: 2.01
67
© Arcteq Relays Ltd