LV1 09 Gesamt EN.book Seite 39 Mittwoch, 11. Februar 2009 3:54 15 Siemens AG 2009 Overload Relays General data Overview Features Benefits 3RU11 3RB20/3RB21 3RB22/3RB23 General data Sizes Are coordinated with the dimensions, connections S00 ...S3 S00 ... S12 S00 ... S12 and technical characteristics of the other devices in the SIRIUS modular system (contactors, soft starters, ...) Permit the mounting of slim and compact load feeders 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 Seamless current range Allows easy and consistent configuration with one 0.11 ... 100 A 0.1 ... 630 A 0.3 ... 630 A 1) series of overload relays (for small to large loads) ( ... 820 A) 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 Provides optimum inverse-time delayed protection () unbalance of loads against excessive temperature rises due to phase unbalance Tripping in the event of phase failure Minimizes heating of induction motors during phase failure Protection of single-phase loads Enables the protection of single-phase loads -- 2) 2) Tripping in the event of overheating Provides optimum temperature-dependent pro- -- -- tection of loads against excessive temperature by rises, e. g. for stator-critical motors or in the event of insufficient coolant flow, contamination of the Integrated thermistor motor motor surface or for long starting or braking oper- protection function ations Eliminates the need for additional special equip- ment Saves space in the control cabinet Reduces wiring outlay and costs Tripping in the event of a ground fault Provides optimum protection of loads against -- high-resistance short-circuits or ground faults due (only 3RB21) by to moisture, condensed water, damage to the insulation material, etc. Internal ground-fault detection Eliminates the need for additional special equip- (activatable) ment. Saves space in the control cabinet Reduces wiring outlay and costs Features RESET function Allows manual or automatic resetting of the relay Remote RESET function Allows the remote resetting of the relay (by means of (only 3RB21 with separate module) 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 correct current value Integrated auxiliary contacts Allows the load to be switched off if necessary (1 NO + 1 NC) (2 ) Can be used to output signals 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. For 3UF18 transformers, see Chapter 7, sectionSIMOCOD. 2) The SIRIUS 3RN thermistor motor protection devices can be used to pro- vide additional temperature-dependent protection. Siemens LV 1 2009 5/39 5LV1 09 Gesamt EN.book Seite 40 Mittwoch, 11. Februar 2009 3:54 15 Siemens AG 2009 Overload Relays General data Features Benefits 3RU11 3RB20/3RB21 3RB22/3RB23 Design of load feeders Short-circuit strength up to 100 kA Provides optimum protection of the loads and op- at 690 V erating personnel in the event of short-circuits due (in conjunction with the corresponding to insulation faults or faulty switching operations fuses or the corresponding motor starter protector) 1) Electrical and mechanical matching Simplifies configuration to 3RT1 contactors Reduces wiring outlay and costs Enables stand-alone installation as well as space- saving direct mounting Straight-through transformers for Reduces the contact resistance -- 2) main circuit (only one point of contact) (S2 ... S6) (S00 ... S6) (in this case the cables are routed Saves wiring costs through the feed-through openings of (easy, no need for tools, and fast) the overload relay and connected Saves material costs directly to the box terminals of the con- tactor) Reduces installation costs -- Spring-loaded terminal connection Enables fast connections -- 2) system for main circuit (S00) Permits vibration-resistant connections Enables maintenance-free connections Spring-loaded terminal connection Enables fast connections 2) system for auxiliary circuits Permits vibration-resistant connections Enables maintenance-free connections Other features Temperature compensation Allows the use of the relays at high temperatures without derating Prevents premature tripping Allows compact installation of the control cabinet without distance between the devices/load feed- ers Simplifies configuration Enables space to be saved in the control cabinet Very high long-term stability Provides safe protection for the loads even after () years of use in severe operating conditions Wide setting ranges Reduce the number of variants -- (1:4) (1:10) Minimize the engineering outlay and costs Minimize storage overhead, storage costs, tied-up capital Trip class CLASS 5 Enables solutions for very fast starting motors re- -- quiring special protection (e. g. Ex motors) (only 3RB21) Trip classes > CLASS 10 Enables heavy starting solutions -- Low power loss Reduces power consumption and energy costs -- (up 98 % less power is used than for thermal over- load relays). Minimizes temperature rises of the contactor and control cabinet in some cases this may eliminate the need for controlgear cabinet cooling. Direct mounting to contactor saves space, even for high motor currents ( i. e. no heat decoupling is required). 1) Exception: up to size S3, only stand-alone installation is possible. 2) Alternatively available for screw terminals. Siemens LV 1 2009 5/40 5