The switch positions used by the operational interlocking logic are obtained from
auxiliary contacts or position sensors. For each end position (open or closed) a true
indication is needed - thus forming a double indication. The apparatus control
function continuously checks its consistency. If neither condition is high (1 or
TRUE), the switch may be in an intermediate position, for example, moving. This
dynamic state may continue for some time, which in the case of disconnectors may
be up to 10 seconds. Should both indications stay low for a longer period, the
position indication will be interpreted as
unknown
. If both indications stay high,
something is wrong, and the state is again treated as
unknown
.
In both cases an alarm is sent to the operator. Indications from position sensors
shall be self-checked and system faults indicated by a fault signal. In the
interlocking logic, the signals are used to avoid dangerous
enable
or
release
conditions. When the switching state of a switching device cannot be determined
operation is not permitted.
For switches with an individual operation gear per phase, the evaluation must
consider possible phase discrepancies. This is done with the aid of an
AND-
function
for all three phases in each apparatus for both open and close indications.
Phase discrepancies will result in an unknown double indication state.
8.3.1
Configuration guidelines
M13529-4 v4
The following sections describe how the interlocking for a certain switchgear
configuration can be realized in the IED by using standard interlocking modules
and their interconnections. They also describe the configuration settings. The
inputs for delivery specific conditions (Qx_EXy) are set to 1=TRUE if they are not
used, except in the following cases:
•
QB9_EX2 and QB9_EX4 in modules BH_LINE_A and BH_LINE_B
•
QA1_EX3 in module AB_TRAFO
when they are set to 0=FALSE.
8.3.2
Interlocking for line bay ABC_LINE
IP14139-1 v2
8.3.2.1
Application
M13561-3 v8
The interlocking for line bay (ABC_LINE) function is used for a line connected to
a double busbar arrangement with a transfer busbar according to figure
function can also be used for a double busbar arrangement without transfer busbar
or a single busbar arrangement with/without transfer busbar.
Section 8
1MRK 511 423-UEN A
Control
128
Bay control REC650 2.2 IEC
Application manual