Overload Relays 3RB2 Solid-State Overload Relays 3RB20, 3RB21 for standard applications 1) For grounded networks, otherwise 600 V. 2) When connecting cable lugs according to DIN 46235, use the 3RT19 56-4EA1 terminal cover for conductor cross-sections from 95 mm 2 to ensure phase spacing. 3) When connecting cable lugs according to DIN 46234 for conductor cross- sections from 240 mm 2 as well as DIN 46235 for conductor cross-sections from 185 mm 2 , use the 3RT19 56-4EA1 terminal cover to ensure phase spacing.
23 Siemens · 2009 Type Size Width 3RB20 56, 3RB21 53 3RB20 66, 3RB21 63 S6 S10/S12 120 mm 145 mm Main circuit Rated insulation voltage Ui V (degree of pollution 3) 1000 Rated impulse withstand voltage Uimp kV 8 Rated operational voltage Ue V 1000 Type of current • Direct current • Alternating current No Yes, 50/60 Hz ±5 % Current setting A 50 ... 200 55 ... 250 to 160 ...
630 Power loss per unit (max.) W 0.05 Short-circuit protection - With fuse without contactor - With fuse and contactor See Catalog LV 1, "Selection and ordering data" See "Technical specifications" (short-circuit protection with fuses for motor feeders) Protective separation between main and auxiliary con- V ducting path acc.
to IEC 60947-1 (degree of pollution 2) 6901) Connection for main circuit Connection type • Terminal screw • Tightening torque Nm • Conductor cross-sections (min./max.), 1 or 2 conductors - Solid mm2 - Finely stranded without end sleeve mm2 - Finely stranded with end sleeve mm2 - Stranded mm2 - AWG cables, solid or stranded AWG - Ribbon cable conductors mm (number x width x thickness) Screw terminals with box terminal 4 mm Allen screw 5 mm Allen screw 10 ... 12 20 ... 22 -- With 3RT19 55-4G box terminal: 2 × (1 × max. 50, 1 × max. 70), 1 × (10 ... 70) With 3RT19 56-4G box terminal: 2 × (1 × max. 95, 1 × max. 120), 1 × (10 ... 120) 2 × (50 ... 185), Front clamping point only: 1 × (70 ...
240) Rear clamping point only: 1 × (120 ... 185) With 3RT19 55-4G box terminal: 2 × (1 × max. 50, 1 × max. 70), 1 × (10 ... 70) With 3RT19 56-4G box terminal: 2 × (1 × max. 95, 1 × max. 120), 1 × (10 ... 120) 2 × (50 ... 185), Front clamping point only: 1 × (70 ... 240) Rear clamping point only: 1 × (120 ... 185) With 3RT19 55-4G box terminal: 2 × (max. 70), 1 × (16 ... 70) With 3RT19 56-4G box terminal: 2 × (max. 120), 1 × (16 ... 120) 2 × (70 ... 240), Front clamping point only: 1 × (95 ... 300) Rear clamping point only: 1 × (120 ... 240) With 3RT19 55-4G box terminal: 2 × (max. 1/0), 1 × (6 ... 2/0) With 3RT19 56-4G box terminal: 2 × (max. 3/0), 1 × (6 ... 250 kcmil) 2 × (2/0 ...
500 kcmil), Front clamping point only: 1 × (3/0 ... 600 kcmil) Rear clamping point only: 1 × (250 kcmil ... 500 kcmil) With 3RT19 55-4G box terminal: 2 × (6 × 15.5 × 0.8), 1 × (3 × 9 × 0.8 ... 6 × 15.5 × 0.8) With 3RT19 56-4G box terminal: 2 × (10 × 15.5 × 0.8), 1 × (3 × 9 × 0.8 ... 10 × 15.5 × 0.8) 2 × (20 × 24 × 0.5), 1 × (6 × 9 × 0.8 ... 20 × 24 × 0.5) Connection type • Terminal screw • Tightening torque Nm • Conductor cross-section (min./max.) - Finely stranded with cable lug mm2 - Stranded with cable lug mm2 - AWG cable, solid or stranded, with cable lug AWG - With connecting bar (max. width) mm Busbar connections M 8 × 25 M 10 × 30 10 ... 14 14 ... 24 16 ... 95 2) 50 ... 240 3) 25 ...
120 2) 70 ... 240 3) 4 ... 250 kcmil 2/0 ... 500 kcmil 15 25 Connection type Diameter of opening mm Straight-through transformers 24.5 --