Ice NP900 Series, Инструкция по применению

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Application Guide - NP900 Series 500 (504
)
A996A
After this is done in the logic editor click Export and then update logic (Commands

Write to relay

Logic

Write).
3.7.7.4 C
LEARING LATCHED SIGNALS
If latched signals are connected to alarms the relay requires the user to push the back
button in the relays front port before it can be cleared. Using latched signals is
generally not advised to keep the clearing of the alarms simple.
3.7.8 F
AULT LOCATOR
(21FL)
Fault locator is used for recording an estimated distance to the point where fault has
occurred. It is mostly used in directional overcurrent protection or distance protection
applications but can be also triggered by other protections as well. Function can be used if
three phase current and three phase voltage have been connected to the relay. In the
configuration the triggering signals, triggering current and reactance per km must be set.
Inputs for the function are the operating mode selections, setting parameters and
measured and pre-processed voltage and current magnitudes and binary input signals.
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. Time stamp resolution is 1ms. Function provides also cumulative counter for
fault locator triggering events.
3.7.8.1 M
EASURED INPUT VALUES
Function block uses analog current and voltage measurements and calculated phase-to-
phase loop impedances.