Arcteq AQ-M255, Инструкция по эксплуатации

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Figure. 7.3 - 184. ARON connection.
The ARON input connection can measure the load symmetrically despite the fact that one of the CTs is
missing from the installation. Normally, Phase 2 does not have a current transformer installed as an
external fault is much more likely to appear on Lines 1 or 3.
A fault between Line 2 and the earth cannot be detected when the ARON input connection is used. In
order to detect an earth fault in Phase 2, a cable core CT must be used.
7.4 Trip circuit supervision (95)
Trip circuit supervision is used to monitor the wiring from auxiliary power supply, through the IED's
digital output, and all the way to the open coil of the breaker. It is recommended to supervise the health
of the trip circuit when breaker is closed.
Trip circuit supervision with one digital input and one non-latched trip output
The figure below presents an application scheme for trip circuit supervision with one digital input and a
non-latched trip output. With this connection the current keeps flowing to the open coil of the breaker
via the breaker's closing auxiliary contacts (52b) even after the circuit breaker is opened. This requires
a resistor which reduces the current: this way the coil is not energized and the relay output does not
need to cut off the coil's inductive current.
A AQ Q-M255 -M255
Instruction manual
Version: 2.06
378 © Arcteq Relays Ltd
IM00020