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AND BURNS. DISCONNECT POWER BEFORE PROCEEDING WITH ANY WORK ON THIS EQUIPMENT. Device description The 3RB12 electronic overload relay protects electrical equipment, such as three-phase AC motors and trans- formers, with three different protection mechanisms. Overload The 3RB12 compares the motor current actually...
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Installation Installation For dimension drawings, see graphics section, Fig. I and II. Mounting position: any Mounting of 70 mm devices: ■ Snap-on mounting on 35 mm mounting rail in con- formity with EN 50 022 or ■ srew mounting by means of inserted lugs as accessory (3RB1900-0B).
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= 1.5 A Protection of If single-phase AC motors are to be protected by the single-phase 3RB12 solid-state overload relay, phase L must be motors looped through the device. The main circuits must be connected as shown in Fig. III.
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Connection 3.1.2 Current range 50 A to 820 A Busbar connection: see graphics section, Fig. II Finely stranded Stranded con- Connection Tightening conductor with ductor with screws torque termination cable lug cable lug [Nm/lb.in] [mm x mm] 3RB1253 35 to 95 50 to 120 10 to 14 / 20 x 4...
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Operation Operation Setting the current ■ Use the current setting range knob to set the appropriate current. Adjust tripping classes Note The motor, leads and contactor must be rated for the appropriate class. Class 10 as delivered. ■ Check the class setting before initial start-up and correct it if necessary! ■...
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Ready LED: Monostable version of device: for operation Dark 95/96, 05/06 open control voltage 97/98, 07/08 closed failure Bistable version of device: Switching statuses are retained Five minutes after overload tripping, the 3RB12 can be reset to operating mode. 3ZX1012-0RB12-1AA1...
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Operation Test Statuses after the Test/Reset button has been pressed: Test Status Without With main current main current* button O.k. Faulty O.k. Faulty Press for LED Ready up to 2 s LED Gen. Fault LED Overload Status of auxiliary unchanged switching elements Press for LED Ready...
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The test with a test time of less than 5 s can be per- formed during operation. In a fault-free state the outputs remain unchanged. Reset When the Reset the overload relay after the following times by 3RB12 has briefly pressing Remote reset automatic-reset tripped because the test / reset...
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Technical data Technical data Specifications DIN VDE 0660 Part 102 / IEC 60947-4-1, DIN VDE 0660 Part 200 / IEC 60947-5-1, UL 508, CSA C 22.2 Pulse packets (burst), IEC 61000-4-4 2 kV Discharge of static electricity, IEC 61000-4-2 8 kV Radiated high-frequency fields, IEC 61000-4-3 3 V/m Surge voltage, IEC 61000-4-5...
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Technical data Short-circuit Main circuit protection Short-circuit protection with fuses for motor feeders with short-circuit currents up to 50 kA at 690 V, 50/60 Hz (see data given in catalog) Control circuit Fuse links, duty class gL/gG 6 A quick-acting 10 A Protective circuit-breaker 1.6 A C characteristic...
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Risque d’électrocution et de brûlure. Isoler cet appareil du réseau avant d’y intervenir pour travaux. Description de l'appareil Le relais électronique de surcharge 3RB12 dispose de différents mécanismes de protection pour les matériels électriques tels que moteurs triphasés et transforma- teurs.