Operate Delay - DEMA 400 Series User Manual

4.3.4.3.3

Operate Delay

The operation delay is the value that determines the characteristic of the protection curve with
the delay type. In the case of Rate of Change of Frequency Protection, the delay type must be
DMT. This delay may take a value between (0.08 – 200) s
4.3.4.3.4 Reset Delay
According to the menu settings, It was selected to count the DMT (fixed time) reset time
(0.04 s) Rate of Change of Frequency Protection above +5 Hz/s without exceeding +5 Hz/s
and without breaker tripping. Thus, after the current falls below the threshold, 40 ms will be
counted. If the threshold is not exceeded until the end of this period, the protection function
trip time counter will be reseted. Reset delay thresholds are in the range of (0-60).
According to the menu settings, exceeding 5 Hz. and without breaker tripping, It was selected
to count the DMT (constant time) reset time (0.04 s) In. rate of change of frequency 5Hz.
Thus, after the current falls below the threshold, 40 ms will be counted. If the threshold is not
exceeded until the end of this period, the protection function trip time counter will be reseted.
Reset delay thresholds are in the range of (0-60).
4.3.5 Power Protection Settings
Voltage Protection Settings can be selected from Menu> Protection Settings> Power
Protection Settings
Relay, the protection of the line / motor power protection briefly; It operates according to the
principle of deactivating the protected part by comparing the current and voltage information
to the relay with the power information assigned in the protection functions.
The function symbols on the device setting screen are shown according to IEC 61850, IEC
60617 and IEEE ANSI standards. Function symbol selection according to these standards:
Menu> System Settings> Function Symbol
• ANSI 32OP - Directional Active Over-Power Protection
• ANSI 32UP - Directional Active Low Power Protection
• ANSI 32OQ - Directional Reactive Over-Power Protection
• ANSI 32UQ - Directional Reactive Low Power Protection
• ANSI 32N - Wattmetric Ground Protection
The power protection settings menu device screen is as follows.
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