ABB Relion 670 Series Product Manual page 19

Busbar protection REB670
Customized
Product version: 1.2
neutral voltages to be connected. For information about how
to connect analog inputs, refer to Application manual/IED
application/Analog inputs/Setting guidelines.
8. Multipurpose protection
General current and voltage protection CVGAPC
The General current and voltage protection (CVGAPC) can be
utilized as a negative or zero sequence current and/or voltage
protection detecting unsymmetrical conditions such as open
phase or unsymmetrical faults.
9. Secondary system supervision
Fuse failure supervision SDDRFUF
The aim of the fuse failure supervision function (SDDRFUF) is
to block voltage measuring functions at failures in the
secondary circuits between the voltage transformer and the
IED in order to avoid unwanted operations that otherwise
might occur.
The fuse failure supervision function basically has three
different algorithms, negative sequence and zero sequence
based algorithms and an additional delta voltage and delta
current algorithm.
The negative sequence detection algorithm is recommended
for IEDs used in isolated or high-impedance earthed
networks. It is based on the negative-sequence measuring
quantities, a high value of voltage 3U
of the negative-sequence current 3I
The zero sequence detection algorithm is recommended for
IEDs used in directly or low impedance earthed networks. It is
based on the zero sequence measuring quantities, a high
value of voltage 3U without the presence of the residual
0
current 3I .
0
For better adaptation to system requirements, an operation
mode setting has been introduced which makes it possible to
select the operating conditions for negative sequence and
zero sequence based function. The selection of different
operation modes makes it possible to choose different
interaction possibilities between the negative sequence and
zero sequence based algorithm.
A criterion based on delta current and delta voltage
measurements can be added to the fuse failure supervision
function in order to detect a three phase fuse failure, which in
practice is more associated with voltage transformer
switching during station operations.
10. Control
Autorecloser SMBRREC
The autoreclosing function provides high-speed and/or
delayed three pole autoreclosing. The autoreclosing can be
ABB
without the presence
2
.
2
used for delayed busbar restoration. One Autorecloser
(SMBRREC) per zone can be made available.
Apparatus control APC
The apparatus control functions are used for control and
supervision of circuit breakers, disconnectors and earthing
switches within a bay. Permission to operate is given after
evaluation of conditions from other functions such as
interlocking, synchrocheck, operator place selection and
external or internal blockings.
Apparatus control features:
• Select-Execute principle to give high reliability
• Selection function to prevent simultaneous operation
• Selection and supervision of operator place
• Command supervision
• Block/deblock of operation
• Block/deblock of updating of position indications
• Substitution of position indications
• Overriding of interlocking functions
• Overriding of synchrocheck
• Operation counter
• Suppression of Mid position
Two types of command models can be used:
• Direct with normal security
• SBO (Select-Before-Operate) with enhanced security
In normal security, the command is processed and the
resulting position is not supervised. However with enhanced
security, the command is processed and the resulting
position is supervised.
Normal security means that only the command is evaluated
and the resulting position is not supervised. Enhanced
security means that the command is evaluated with an
additional supervision of the status value of the control
object. The command security with enhanced security is
always terminated by a CommandTermination service
primitive.
Control operation can be performed from the local HMI under
authority control if so defined.
Logic rotating switch for function selection and LHMI
presentation SLGGIO
The logic rotating switch for function selection and LHMI
presentation (SLGGIO) (or the selector switch function block)
is used to get a selector switch functionality similar to the one
provided by a hardware selector switch. Hardware selector
switches are used extensively by utilities, in order to have
different functions operating on pre-set values. Hardware
switches are however sources for maintenance issues, lower
system reliability and an extended purchase portfolio. The
logic selector switches eliminate all these problems.
1MRK505273-BEN D
19