Technical data
11.2 Performance features
SIRIUS Innovations - SIRIUS 3RU2 thermal overload relays / SIRIUS 3RB3 solid-state overload relays
Manual, 09/2014, A5E03656507420A/RS-AA/002
105
11.2.2
Protection functions - overview
Table 11- 2 Protection functions supported by 3RU21 and 3RB30/3RB31 overload relays
Feature
Description
3RU21
3RB30/3RB31
Tripping in the event of overload
•
Provides optimum current-dependent
protection of loads against impermissibly high
temperature rise due to overload
✓
✓
Tripping in the event of phase
asymmetry
•
Provides optimum current-dependent
protection of loads against impermissibly high
temperature rise due to phase asymmetry
✓
✓
Tripping in the event of phase failure
•
Minimizes the temperature rise of the three-
phase motor in the event of a phase failure
✓
✓
Protection of single-phase loads
•
Enables single-phase loads to be protected
✓
--
Tripping in the event of ground fault
by means of
internal ground-fault detection (can
be activated)
•
Provides optimum protection of loads in the
event of high-impedance faults to ground
caused by moisture, condensation, damaged
insulation, etc.
•
Eliminates the need for additional special
equipment
•
Saves space in the control cabinet
•
Reduces wiring time and wiring costs
--
✓
(3RB31 only)