Protection Equipment Introduction Overload Relays General data - Overview 3RU1 Thermal Overload Relays 3RU11 for standard applications - Overview - Design - Function - Technical specifications - Characteristic curves - Dimensional drawings - Schematics Accessories 3RB2 Solid-State Overload Relays 3RB20, 3RB21 for standard...
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2) Size S3 up to 1000 V AC. 3) Size S2 (only with straight-through transformer), S3, S6, S10, S12 up to 1000 V AC. 4) With reference to the 3RB29 .6 current measuring modules. 5) Stand-alone installation without accessories is possible. Siemens · 2011...
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. Siemens · 2011...
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• 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 · 2011...
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• Saves space in the control cabinet • Reduces wiring outlay and costs 1) The SIRIUS 3RU11 thermal overload relays use a bimetal contactor and therefore do not require a control supply voltage. Siemens · 2011...
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(box terminals) or spring-type terminals on the auxiliary current side; the same applies for the evaluation modules of the 3RB22/3RB23 relays. The 3RU11 relays come with screw terminals. Screw terminals (box terminals) Spring-type terminals These connections are indicated in the Technical specifications by orange backgrounds.
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An over- The 3RU11 thermal overload relays up to 100 A have been desi- load relay mounted onto the line contactor must be set to 0.58 gned for inverse-time delayed protection of loads with normal st- times the motor current.
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3RU11 thermal overload relays with/without contactor This tests whether the auxiliary circuit has been correctly connec- see "Technical specifications" and Catalog LV 1, "Selection and or- ted to the overload relay. If the 3RU11 thermal overload relay has dering data".
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Overload Relays 3RU1 Thermal Overload Relays 3RU11 for standard applications ■ Technical specifications Type 3RU11 16 3RU11 26 3RU11 36 3RU11 46 Size Width 45 mm 45 mm 55 mm 70 mm General data Trips in the event of Overload and phase failure Trip class acc.
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2) Terminal compartment: degree of protection IP00. 2) If two different conductor cross-sections are connected to one clamping 3) The 3RU11 16 overload relay with Cage Clamp terminals can only be ins- point, both cross-sections must lie in the range specified. If identical cross- talled as a stand-alone installation.
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Overload Relays 3RU1 Thermal Overload Relays 3RU11 for standard applications Type 3RU11 16 3RU11 26 3RU11 36 3RU11 46 Size Width 45 mm 45 mm 55 mm 70 mm Auxiliary circuit Number of NO contacts Number of NC contacts Auxiliary contacts – assignment 1 NO for the signal "tripped",...
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Overload Relays 3RU1 Thermal Overload Relays 3RU11 for standard applications Short-circuit protection with fuses/motor starter protectors for motor feeders With short-circuit currents up to 100 kA at rated operational voltages up to AC 50/60 Hz 690 V Permissible short-circuit protection fuse for motor starters comprising overload relay and contactor, type of coordination 2...
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Overload Relays 3RU1 Thermal Overload Relays 3RU11 for standard applications Short-circuit protection with fuses/motor starter protectors for motor feeders With short-circuit currents up to 100 kA at rated operational voltages up to AC 50/60 Hz 690 V Permissible short-circuit protection fuse for motor starters comprising overload relay and contactor, type of coordination 2 15 kW r 3RT10 34 18.5 kW r 3RT10 35...
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To avoid damage, three-pole loads are between 105 and 120 % of the current the 3RU11 thermal overload relays are fitted with phase failure setting. sensitivity which ensures faster tripping in accordance with the...
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Overload Relays 3RU1 Thermal Overload Relays 3RU11 for standard applications ■ Dimensional drawings Screw connection 3RU11 36-..B. Size S2, with terminal bracket for stand-alone installation Lateral distance to grounded components: at least 6 mm. 3RU11 16-..B0 Size S00, with mechanical RESET min.
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4 T 2 6 T 3 1 4 / 2 2 1 ) R e m o t e R E S E T 3RU11 26 to 3RU11 46 3RU11 26-..D. Size S0, with terminal bracket for stand-alone installation 4 , 5...
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3RU1 Thermal Overload Relays Accessories ■ Overview The following accessories are available for the 3RU11 thermal • One mechanical RESET module for all sizes overload relays: • One cable release for resetting devices which are difficult to • For the four overload relay sizes S00 to S3 one terminal bra-...
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The "tripped" status is signaled by means of a switch position in- quency converter, Siemens recommends the 3RN thermistor mo- dicator. Resetting takes place either manually or automatically af- tor protection devices or the 3RU11 thermal overload relays for ter the recovery time has elapsed (see "Function").
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RESET by applying a voltage of 24 V DC to the terminals A3 and A4. If the slide switch is set to automatic RESET, the relay is reset automatically. The time between tripping and resetting is determined by the recovery time. Siemens · 2011...
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2) S0 for 6 ... 25 A, CLASS 20, = 19 A; 4) Terminal compartment: degree of protection IP00. emax S0 for 6 ... 25 A, CLASS 30, = 16 A. emax 5) Signaling contact 97/98 in position "tripped": 4/11 g/ms. Siemens · 2011...
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3) For grounded networks, otherwise 600 V. 4) If two different conductor cross-sections are connected to one clamping point, both cross-sections must lie in the range specified. If identical cross-sections are used, this restriction does not apply. Siemens · 2011...
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3) When connecting cable lugs according to DIN 46234 for conductor cross- sections from 240 mm as well as DIN 46235 for conductor cross-sections from 185 mm , use the 3RT19 66-4EA1 terminal cover to ensure phase spa- cing. Siemens · 2011...
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6) With 3UF18 68-3GA00 current transformer. Type of coordination "2": The contactor or the starter must be operatio- nal after a release (without replacement of parts). There is a risk of contact welding. Siemens · 2011...
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The above illustrations are schematic representations of charac- teristic curves. The characteristic curves of the individual 3RB20/3RB21 electronic overload relays can be ordered from "Technical Assistance": • Either by e-mail to: technical-assistance@siemens.com • Or on the Internet at: http://www.siemens.com/automation/service&support Siemens · 2011...
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3 L 2 5 L 3 1 L 1 3 L 2 5 L 3 ( ) 2 4 V 2 T 1 4 T 2 6 T 3 2 T 1 4 T 2 6 T 3 ( + ) Siemens · 2011...
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AS-i bus system. The devices are manufactured in accordance with environmental guidelines and contain environmentally friendly and reusable ma- terials. They comply with all important worldwide standards and approvals. 3RB29 06 current measuring module Siemens · 2011...
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If motor protection is required on the outgoing side of the fre- specifications" and Catalog LV 1, "Selection and ordering data". quency converter, Siemens recommends the 3RN thermistor motor protection devices or the 3RU11 thermal overload relays for this purpose. Siemens · 2011...
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Fuses or motor starter protectors must be used for short-circuit protection. For assignments of the corresponding short-circuit protection de- vices to the 3RB22/3RB23 solid-state overload relays with/without contactor see "Technical specifications" and Catalog LV 1, "Selection and ordering data". Siemens · 2011...
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C o n t a c t o r o p e n C o n t a c t o r c l o s e d Siemens · 2011...
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S00 to S3: stand-alone installation, current measuring module size S6 and S10/S12: stand-alone installation and moun- ting onto contactors 1) On request. 2) Current measuring modules size S6 and S10/S12 with busbar connection in conjunction with cover. Siemens · 2011...
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2) When connecting cable lugs according to DIN 46235, use the from 185 mm , use the 3RT19 56-4EA1 terminal cover to ensure phase 3RT19 56-4EA1 terminal cover for conductor cross-sections from 95 mm spacing. to ensure phase spacing. Siemens · 2011...
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2 × (0.25 ... 1.5) - Stranded 2 × (0.25 ... 1.5) 2 × (24 ... 16) - AWG cables, solid or stranded 1) The assignment of auxiliary contacts may be influenced by function expan- sion modules. Siemens · 2011...
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4) Analog input modules, e. g. SM 331, must be configured for 4-wire measuring transducers. In this case the analog input module must not 2) Sensor circuit. supply current to the analog output of the 3RB22/3RB23 relay. 3) In conjunction with corresponding function expansion module. Siemens · 2011...
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(without replacement of parts). There is a risk of contact welding. 3) Contactors not mountable. 4) Please ensure that the maximum AC-3 operational current has sufficient safety clearance from the rated current of the fuses. 5) With 3UF18 68-3GA00 current transformer. Siemens · 2011...
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The above illustrations are schematic representations of charac- teristic curves. The characteristic curves of the individual 3RB22/3RB23 electronic overload relays can be ordered from "Technical Assistance": • Either by e-mail to: technical-assistance@siemens.com • Or on the Internet at: http://www.siemens.com/automation/service&support Siemens · 2011...
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3RB22 83-..., 3RB23 83-... 3RB29 .6-... READY CLASS RESET 5, 10, 20, 30 FAULT 3RB29 87-2. AUTO THER- Ground MISTOR Fault OVER- LOAD T1 T2 T3 T1 T2 I(-) I(+) 96/05 98/07 REMOTE- 4-20 mA U V W RESET NSB0_01527a Siemens · 2011...
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Overload warning Overload warning contactor (inverse- "tripped" time delayed/tempe- rature-dependent protection + ground fault) 3RB29 85-2AB1 Analog signal Disconnection of the Signal Switching off the Signal contactor (inverse- "tripped" contactor (ground "ground-fault time delayed/tempe- fault) tripping" rature-dependent protection) Siemens · 2011...