Siemens siprotec 7SA6 User Manual

Configuration
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7SA6 Manual
C53000-G1176-C156-2
5.2.6 Settings for Contact Chatter Blocking
Contact Chatter
Suppression
The contact chatter filter checks whether the number of condition changes at a binary
input exceeds a preset value during a predetermined time interval. If this occurs, the
binary input will be blocked for a certain time, so the event list does not contain a large
number of unnecessary entries. The setting values necessary for this feature may be
entered in a dialogue box, as shown in Figure 5-33. This dialogue box can be found
from the open configuration matrix by clicking Options in the menu bar and then se-
lecting Chatter Blocking.
Figure 5-33 DIGSI
®
4: Setting the chatter blocking feature
Defining the Moni-
toring Criteria
The operating mode of the chatter blocking feature is determined by five settings:
• Number of permissible state changes
This setting establishes how often the state of a binary input within the Initial
Test Time may change. If this number is exceeded, the binary input is or remains
blocked. If the setting is 0 the chatter blocking is disabled.
• Initial test time
Within this time interval (in seconds), the number of state changes of a binary input
is checked. The time interval begins with the first activation of a signal to the binary
input.
• Number of chatter tests
This number represents how many check cycles should be conducted before the
binary input is finally blocked. Please consider that even a high set value can be
reached over the normal life span of the device and could lead to blocking of the
binary input. Therefore this value can also be set to infinity. For this, enter the char-
acter sequence of oo.
• Chatter Idle Time
If the Number of permissible state changes at a binary input is exceeded
during the Initial test time or the Subsequent test time,theChatter
idle time interval is initiated. The affected binary input is blocked for this time
interval. The Chatter idle time setting is entered in minutes. This settings can
only be programmed if the Number of chatter tests is not set to zero.
• Subsequent test time – Within this time interval, the number of state changes
at a binary input is checked again. This interval begins after the Chatter idle
time interval has expired. If the number of state changes is within allowable limits,
the binary input is released. Otherwise, the idle interval is restarted, until the maxi-
mum Number chatter tests is reached again. The Subsequent test time
setting is entered in seconds. This settings can only be programmed if the Number
of chatter tests is not set to zero.

Siemens siprotec 7SA6 Specifications

General

Brand	Siemens
Model	siprotec 7SA6
Category	Relays
Language	English