Functions
2.12 Circuit-Breaker Test
SIPROTEC, 7SD80, Manual
E50417-G1140-C474-A1, Release date 09.2011
159
For Automatic Reclosing and Circuit-Breaker Test
Separate binary inputs comprising information on the position of the circuit breaker are available for the auto-
matic reclosing function and the circuit-breaker test. This is important for
• the plausibility check before automatic reclosing (refer to Section 2.11),
• the trip circuit check with the help of the TRIP-CLOSE test cycle (refer to Section 2.12).
When using 1
1
/
2
or 2 circuit breakers in each feeder, the automatic reclosure function and the circuit-breaker
test are referred to
one
circuit breaker. The feedback information of this circuit breaker can be connected sep-
arately to the device.
Separate binary inputs are available to this end which should be treated in the same way and configured addi-
tionally if necessary. These have a similar significance as the inputs described above for protection applications
and are marked with „CB1 ...“ to distinguish them, i.e.:
•
„>52a Bkr1 3p Cl“
(no. 410) for the series connection of the NO auxiliary contacts,
•
„>52b Bkr1 3p Op“
(no. 411) for the series connection of the NC auxiliary contacts,
2.12.3
Circuit-Breaker Test
The 7SD80 differential protection enables the trip circuits and circuit breakers to be tested conveniently.
For the test, a 3-pole TRIP/CLOSE cycle and the close command
„CB1-TEST close“
(7329) are performed
via the test program.
The output indication
„CB1-TESTtripABC“
(7328) must be routed to the command relays used to control the
circuit-breaker coils.
The test is started using the operator panel on the front of the device or using the PC with DIGSI. The procedure
is described in detail in the SIPROTEC 4 System Description. Figure 2-63 shows the chronological sequence
of one TRIP-CLOSE test cycle. The set times are those stated in Section 2.1.3.1 for „Trip Command Duration“
and „Circuit-breaker Test“.
If the circuit-breaker auxiliary contacts forward the CB position to the device via binary inputs, the test cycle can
only be initiated when the circuit breaker is closed.
The information on the circuit-breaker position is not automatically derived from the position logic according to
the above section. For the circuit-breaker test, there are separate binary inputs for position feedback. These
must be taken into consideration when routing the binary inputs.
The device generates indications that show the corresponding test status.
Figure 2-63
TRIP-CLOSE test cycle
