Lower Threshold Value - Siemens SIRIUS 3RT Series System Manual

8.8.1.2

Lower threshold value

Definition of lower threshold value (I▼)
Setting the threshold value for current undershoot If one of the monitored parameters
undershoots this threshold value, the current monitoring relay will disconnect once the set
tripping delay time (Del, see the chapter titled Tripping delay time (Page 708)) has elapsed.
Setting range
The setting range for the lower threshold value (I▼) is OFF as well as continuously 1.6 A to
16 A (3RR2141-.A.30) or 4 A to 40 A (3RR2142-.A-30).
Note
Setting OFF selects "Current overshoot" monitoring mode, see the chapter titled Upper
threshold value (Page 706).
Factory setting
The lower threshold value is deactivated in the factory setting.
Changes to settings
Changes to the lower threshold value can be made by adjusting the corresponding rotary
button (I▼) with a screwdriver.
NOTICE
Deactivating monitoring
If both threshold values are deactivated (OFF), monitoring will cease.
 Current overshoot
 Current undershoot
The following parameters continue to be monitored:
 Phase failure
SIRIUS Innovations
System Manual, 01/2011, A8E56203870002-03
SIRIUS 3RR2 current monitoring relays
8.8 Operation
705