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7SV512
V1
6.5.3
Off/On control of part functions of the device
During operation of protection relay it may be de-
sired to control the relay manually or from system cri-
teria, temporarily to switch off partial functions of the
relay or to switch them on only under specific condi-
tions. An example may be the switching off the pro-
tection function during maintenance of the circuit
breaker.
The relay allows partial functions to be switched on
or off via binary inputs or manual operation via the
integrated operator panel or via the operating inter-
face at the front using a personal computer.
For switching via binary inputs it is, of course, neces-
sary that the binary inputs have been marshalled to
the corresponding switching functions. Further-
more, it must be noted that a binary input is required
for each function, switching off and switching on.
The switching command is stored in the relay and
protected against auxiliary voltage failure (the func-
tion of a bi-stable store). The command can be an-
nunciated via an annunciation relay or LED display.
For switching via the integrated operator panel or
the front interface, a code word is necessary. The
control functions are found at the beginning of the
parameter block of each protection or supplementa-
ry function. The switch condition shown in the dis-
play can be changed over using the "No"---key N.
The opposite switch condition then appears in the
display. Each change of condition must be con-
firmed with the E---key. The change-over is first re-
corded in the relay when codeword operation has
been terminated. This is done by the key combina-
tion F E, i.e. depressing the function key F followed
by the entry key E. The display shows the question
"SAVE NEW SETTINGS?". Confirm with the
"Yes"---key J/Y that the new settings shall become
valid now. The switched conditions are then perma-
nently stored in EEPROMs and protected against
auxiliary voltage failure; the display confirms "NEW
SETTINGS SAVED". If you press the "No"---key N in-
stead, codeword operation will be aborted, i.e. all al-
terations which have been changed since the last
codeword entry are lost. Thus, erroneous alterations
can be made ineffective.
A function is switched ON when the on---command
has been given by both the binary input AND also
from the operator panel or interface.
C53000---G1176---C91
A function is switched OFF when the off---command
is given by EITHER the binary input OR from the op-
erator panel or the operating interface. Thus it is en-
sured that a partial function can only be switched on
from that place where it was previously switched off.
Control inputs which are not marshalled to a binary
input are regarded, from that location, as switched
on, so that change of the condition is possible from
the operator panel or the operating interface.
At the operator panel and the operating interface the
factory setting is equally that all partial functions are
switched on, so that switching via binary inputs is
possible.
The completion of a switching command is, inde-
pendent of its cause, output as an operational an-
nunciation:
--- "(function) off" Comes at the instant of
switch-off,
--- "(function) off" Goes at the instant that it is
switched on.
These annunciations are listed in block 51 under
OPERATIONAL ANNUNCIATIONS and can also be
transmitted via the LSA interface to a central com-
puter. Also they can be marshalled as binary out-
puts; the signal relay then indicates the switched-off
condition.
For annunciations one must differentiate:
--- Direct confirmation of a binary input is available as
long as the corresponding binary input is ener-
gized. It can be output via a signal relay or LED. In
the summary of all annunciations (Appendix C)
these annunciations are identified with a '>' sym-
bol.
--- The completion indication of the switched-off con-
dition is signalized independently of the source of
the command. It appears ("Comes") at the instant
of switch-off and disappears ("Goes") at the in-
stant of switching on.
The following survey shows the control functions
and also indicates which confirmation indications
are generated.
Operating instructions
95
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