Name
Range
Step
Default
Description
Curve 1...4 input
-1 000
000.00...1 000
000.00
0.00001 -
Displays the input measurement received by the curve.
Curve1...4 input
maximum
-1 000
000.00...1 000
000.00
0.00001 0
Defines the maximum input of the curve. If input is above the
set limit, "ASC1...4 input out of range" is activated.
Curve1...4 output
-1 000
000.00...1 000
000.00
0.00001 -
Displays the output of the curve.
The input signal filter (see the image below) calculates the average of received signals according to the
set time constant. This is why rapid changes and disturbances (such as fast spikes) are smothered.
The Nyquist rate states that the filter time constant must be at least double the period time of the
disturbance process signal. For example, the value for the filter time constant is 2 seconds for a 1
second period time of a disturbance oscillation.
When the curve signal is out of range, it activates the "ASC1...4 input out of range" signal, which can
be used inside logic or with other relay functions. The signal can be assigned directly to an output relay
or to an LED in the I/O matrix. The "Out of range" signal is activated, when the measured signal falls
below the set input minimum limit, or when it exceeds the input maximum limit. The "Out of range"
signal is very useful when e.g. a 4…20 mA input signal is used (see the image below).
If for some reason the input signal is lost, the value is fixed to the last actual measured cycle value. The
value does not go down to the minimum if it has been something else at the time of the signal breaking.
A
AQ
Q-M255
-M255
Instruction manual
Version: 2.06
© Arcteq Relays Ltd
IM00020
313
Summary of Contents for AQ-M255
Page 1: ...AQ M255 Motor protection IED Instruction manual...
Page 2: ......
