ABB RELION 670 Series Product Manual page 25

Bay control REC670 2.1 IEC
CCRBRF can be single- or three-phase initiated to allow
use with single phase tripping applications. For the
three-phase version of CCRBRF the current criteria can
be set to operate only if two out of four for example,
two phases or one phase plus the residual current start.
This gives a higher security to the back-up trip
command.
CCRBRF function can be programmed to give a single- or
three-phase re-trip of its own breaker to avoid
unnecessary tripping of surrounding breakers at an
incorrect initiation due to mistakes during testing.
Stub protection STBPTOC
When a power line is taken out of service for
maintenance and the line disconnector is opened in
multi-breaker arrangements the voltage transformers
will mostly be outside on the disconnected part. The
primary line distance protection will thus not be able to
operate and must be blocked.
The stub protection STBPTOC covers the zone between
the current transformers and the open disconnector.
The three-phase instantaneous overcurrent function is
released from a normally open, NO (b) auxiliary contact
on the line disconnector.
Pole discordance protection CCPDSC
An open phase can cause negative and zero sequence
currents which cause thermal stress on rotating
machines and can cause unwanted operation of zero
sequence or negative sequence current functions.
Normally the own breaker is tripped to correct such a
situation. If the situation persists the surrounding
breakers should be tripped to clear the unsymmetrical
load situation.
The Pole discordance protection function CCPDSC
operates based on information from auxiliary contacts
of the circuit breaker for the three phases with
additional criteria from unsymmetrical phase currents
when required.
Directional over/underpower protection GOPPDOP/
GUPPDUP
The directional over-/under-power protection
GOPPDOP/GUPPDUP can be used wherever a high/low
active, reactive or apparent power protection or
alarming is required. The functions can alternatively be
used to check the direction of active or reactive power
flow in the power system. There are a number of
applications where such functionality is needed. Some
of them are:
• detection of reversed active power flow
• detection of high reactive power flow
Each function has two steps with definite time delay.
ABB
Broken conductor check BRCPTOC
The main purpose of the function Broken conductor
check (BRCPTOC) is the detection of broken conductors
on protected power lines and cables (series faults).
Detection can be used to give alarm only or trip the line
breaker.
Voltage-restrained time overcurrent protection
VRPVOC
Voltage-restrained time overcurrent protection
(VRPVOC) function can be used as generator backup
protection against short-circuits.
The overcurrent protection feature has a settable
M12902-3 v9
current level that can be used either with definite time
or inverse time characteristic. Additionally, it can be
voltage controlled/restrained.
One undervoltage step with definite time characteristic
is also available within the function in order to provide
functionality for overcurrent protection with
undervoltage seal-in.
Capacitor bank protection (CBPGAPC)
Shunt Capacitor Banks (SCB) are used in a power system
to provide reactive power compensation and power
factor correction. They are as well used as integral parts
of Static Var Compensators (SVC) or Harmonic Filters
M13269-3 v14
installations. Capacitor bank protection (CBPGAPC)
function is specially designed to provide protection and
supervision features for SCBs.
6. Voltage protection
Two step undervoltage protection UV2PTUV
Undervoltages can occur in the power system during
faults or abnormal conditions. Two step undervoltage
protection (UV2PTUV) function can be used to open
circuit breakers to prepare for system restoration at
power outages or as long-time delayed back-up to
primary protection.
UV2PTUV has two voltage steps, each with inverse or
SEMOD175421-4 v6
definite time delay.
UV2PTUV has a high reset ratio to allow settings close to
system service voltage.
Two step overvoltage protection OV2PTOV
Overvoltages may occur in the power system during
abnormal conditions such as sudden power loss, tap
changer regulating failures, and open line ends on long
lines.
Two step overvoltage protection (OV2PTOV) function
can be used to detect open line ends, normally then
1MRK 511 361-BEN D
SEMOD171446-5 v2
GUID-935E1CE8-601F-40E2-8D22-2FF68420FADF v6
GUID-D55CEBF7-9377-4E36-BD8B-533609048A1E v2
M13789-3 v11
M13798-3 v14
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