Overload Relays General data Overview 1) Motor currents up to 820 A can be recorded and evaluated by a current measuring module, e. g. 3RB29 06-2BG1 (0.3 ... 3 A), in combination with a 3UF18 68-3GA00 (820 A/1 A) series transformer. 2) The SIRIUS 3RN thermistor motor protection devices can be used to pro- vide additional temperature-dependent protection.
4 Siemens · 2009 Features Benefits 3RU11 3RB20/3RB21 3RB22/3RB23 3RU11 3RB20/3RB21 3RB22/3RB23 General data Sizes • Are coordinated with the dimensions, connections and technical characteristics of the other devices in the SIRIUS modular system (contactors, soft starters, ...) • Permit the mounting of slim and compact load fee- ders in widths of 45 mm (S00), 45 mm (S0), 55 mm (S2), 70 mm (S3), 120 mm (S6) and 145 mm (S10/S12) • Simplify configuration S00 ...S3 S00 ... S12 S00 ... S12 Seamless current range • Allows easy and consistent configuration with one series of overload relays (for small to large loads) 0.11 ... 100 A 0.1 ... 630 A 0.3 ... 630 A (...
820 A)1) Protection functions Tripping in the event of overload • Provides optimum inverse-time delayed protection of loads against excessive temperature rises due to overload ✔ ✔ ✔ Tripping in the event of phase unbalance • Provides optimum inverse-time delayed protection of loads against excessive temperature rises due to phase unbalance (✔) ✔ ✔ Tripping in the event of phase failure • Minimizes heating of induction motors during pha- se failure ✔ ✔ ✔ Protection of single-phase loads • Enables the protection of single-phase loads ✔ -- ✔ Tripping in the event of overheating by integrated thermistor motor protection function • Provides optimum temperature-dependent pro- tection of loads against excessive temperature rises, e.
g. for stator-critical motors or in the event of insufficient coolant flow, contamination of the motor surface or for long starting or braking opera- tions • Eliminates the need for additional special equipment • Saves space in the control cabinet • Reduces wiring outlay and costs --2) --2) ✔ Tripping in the event of a ground fault by internal ground-fault detection (activatable) • Provides optimum protection of loads against high-resistance short-circuits or ground faults due to moisture, condensed water, damage to the in- sulation material, etc. • Eliminates the need for additional special equipment.
• Saves space in the control cabinet • Reduces wiring outlay and costs -- ✔ (only 3RB21) ✔ Features RESET function • Allows manual or automatic resetting of the relay ✔ ✔ ✔ Remote RESET function • Allows the remote resetting of the relay ✔ (by means of sepa- rate module) ✔ (only 3RB21 with 24 V DC) ✔ TEST function for auxiliary contacts • Allows easy checking of the function and wiring ✔ ✔ ✔ TEST function for electronics • Allows checking of the electronics -- ✔ ✔ Status display • Displays the current operating state ✔ ✔ ✔ Large current adjustment button • Makes it easier to set the relay exactly to the cor- rect current value ✔ ✔ ✔ Integrated auxiliary contacts (1 NO + 1 NC) • Allows the load to be switched off if necessary • Can be used to output signals ✔ ✔ ✔ (2 ×)