Figure 4.9-1 Logic Diagram: Circuit Breaker Status - Siemens 7SR21 Manual

7SR21 & 7SR22 Argus Description of Operation
Blocked Close Delay
The close command may be delayed by a Block Close CB signal applied to a binary input. This causes the
feature to pause before it issues the CB close command and can be used, for example, to delay CB closure until
the CB energy has reached an acceptable level. If the Block signal has not been removed before the end of the
defined time, Blocked Close Delay, the relay will go to the lockout state.
Open CB Delay
The Open CB Delay setting is applicable to CB trip commands received through an Open CB binary input or via
the Control Menu. Operation of the Open CB binary output is delayed by the Open CB Delay setting.
Open CB Pulse
The duration of the CB open Command pulse is user settable to allow a range of CBs to be used.
CB Failed To Open is taken from the Circuit Breaker Failure Element.
CB Travel Alarm (DBI)
The CB Open/CB Closed binary inputs are monitored. The relay goes to Lockout and an output can be given
where a 0/0 condition exists for longer than the CB Travel Alarm setting.
An instantaneous output is given for a 1/1 state.
Hot Line In/Out
When 'Hot Line' is enabled all auto reclose sequences are inhibited and any fault causes an instantaneous trip to
lockout.

Figure 4.9-1 Logic Diagram: Circuit Breaker Status

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