Circuit Breaker Test
CB Close Detection
During energization of the protected object, several measures may be required or desirable. Following a
manual closure onto a short circuit, immediate trip of the circuit breaker is usually desired. This is done, e.g. in
the overcurrent protection by bypassing the time delay of a current element. For each protection function
which can be delayed, at least one element can be selected that will operate instantaneously in the event of
closing, as mentioned in the relevant sections. See also Section 2.1.6.1 Setting Notes at margin heading
“Circuit-Breaker Status”.
The manual closing command must be indicated to the device via a binary input. In order to be independent
of the individual manual actuation, the command is set to a defined length in the device (adjustable with the
address 1150 SI Time Man.Cl). This setting can only be changed using DIGSI at Display Additional
Settings. The following figure shows the logic diagram.
[lo-hand-ein-011010, 2, en_US]
Figure 2-58 Logic diagram of the manual CLOSE procedure
Reclosing via the integrated local control or control using DIGSI can have the same effect as manual reclosure
(parameter 1152 Section 2.1.6.1 Setting Notes under margin heading “Circuit-Breaker Status”.
If the device has an integrated automatic reclosure, the integrated manual closure logic of the 7SD80 auto-
matically distinguishes between an external control command via the binary input and an automatic reclosure
by the internal automatic reclosure so that the binary input
>Manual Close
can be connected directly to the
control circuit of the close coil of the circuit breaker (Figure 2-59). Each reclosure that is not initiated by the
internal automatic reclosure function is interpreted as a manual reclosure, even it has been initiated by a
control command from the device.
With the user-definable logic functions (CFC) further control functions can be processed in the same way as a
manual close command.
2.12
2.12.1
Functions
2.12 Circuit Breaker Test
142 SIPROTEC 4, 7SD80, Manual
E50417-G1100-C474-A2, Edition 02.2018
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