Tripping Delay Time - Siemens SIRIUS 3RT Series System Manual

SIRIUS 3RR2 current monitoring relays
8.8 Operation
8.8.1.5

Tripping delay time

Definition of tripping delay time (Del)
The set tripping delay time starts when the monitoring current overshoots or undershoots the
corresponding set threshold value.
Explanation
The set tripping delay time starts when the load current flowing under normal operating
conditions overshoots or undershoots the corresponding set threshold value. The red FAULT
LED flashes. Once this time has elapsed, the switching contact changes the switching state
and the FAULT LED lights up continuously if the current value is still outside the correct
range. As a result, transient current oscillations are ignored and do not lead to undesirable
switching operations (alarms, for example).
Note
Special cases wire break/phase failure
A delay time is not observed if a wire break or phase failure is detected. The current
monitoring relay responds immediately (≤ 300 ms) in such cases.
Setting range
The setting range for the tripping delay is continuously 0 s to 30 s.
Factory setting
The tripping delay is factory-set to 0 s.
Changes to settings
Changes to the tripping delay time can be made by adjusting the corresponding rotary button
(Del) with a screwdriver.
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SIRIUS Innovations
System Manual, 01/2011, A8E56203870002-03