Siemens SIRIUS 3RU2 - Protection Functions - Overview

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)