Siemens Argus 7SR11 Manual Download

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7SR11 & 7SR12 Description Of Operation

4.2 Manual CB Control

CB Control is not supported by the 7SR1102-1*A12-*AA0 models with ‘A’ variant software.

A Manual Close Command can be initiated in one of three ways: via a

Close CB

binary input, via the data

communication Channel(s) or from the relay CONTROL MODE menu. It causes an instantaneous operation via

Manual Close CB

binary output, over-riding any DAR sequence in progress.

Repeated Manual Closes are avoided by checking for Positive edge triggers. Even if the Manual Close input is
constantly energised the relay will only attempt one close.

A Manual Close will initiate Line Check if

Line Check Trip

is enabled. If a fault appears on the line during the

Close Pulse or during the Reclaim Time with Line Check enabled, the relay will initiate a Trip and Lockout. This
prevents a CB being repeatedly closed onto a faulted line. Where

Line Check Trip

DELAYED

then

instantaneous protection is inhibited until the reclaim time has elapsed.

Manual Close resets Lockout, if the conditions that caused Lockout have reset, i.e. there is no trip or Lockout
input present.

Manual Close cannot proceed if there is a Lockout input present.

With the Autoreclose function set to Disabled the Manual Close control is still active.

Close CB Delay

The Close CB Delay is applicable to manual CB close commands received through a

Close CB

binary input or

via the Control Menu. Operation of the

Manual Close CB

binary output is delayed by the

Close CB Delay

setting. The status of this delay is displayed on the relay fascia as it decrements towards zero. Only when the
delay reaches zero will the close command be issued and related functionality initiated.

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. The output

Close CB Blocked

indicates this condition.

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. The status

of this delay is displayed on the relay fascia as it decrements towards zero. Only when the delay reaches zero will
the trip command be issued and related functionality initiated.

It should be noted that a CB trip initiated by an

Open CB

command is fundamentally different from a CB trip

initiated by a protection function. A CB trip caused by a

CB Open

command will not initiate functionality such as

circuit-breaker fail, fault data storage, I

t measurement and operation counter.

CB Controls Latched

CB controls for manually closing and tripping can be latched for extra security.

With Reset operation, the control resets when the binary input drops off. This can lead to multiple control restarts
due to bounce on the binary input signal.

With Latch operation, the close or trip sequence always continues to completion (or sequence failure) and bounce
on the binary input is ignored.

Reset operation can be useful, however, as it allows a close or trip sequence to be aborted by dropping off the
binary input signal.