Solid-state overload relay, CLASS 20E, contactor-mounted
The Siemens 3RB2015-2PB0 is a SIRIUS solid-state overload relay (product designation per) with trip class CLASS 20E, designed for contactor mounting. It provides motor protection for three-phase AC loads up to 690 V AC-3 rated maximum.
Electrical ratings and auxiliary contact capacity
Auxiliary contact ratings are specified at multiple control voltages: 2 A at 24 V, 4 A at 120 V, and 3 A at 230 V. For DC switching, the relay carries 0.55 A at 60 V, 0.3 A at 110 V, 0.3 A at 125 V, and 0.11 A at 220 V. These values govern the maximum switched current in the control circuit; the relay provides no built-in auxiliary contacts.
Environmental, EMC, and ATEX compliance
The relay is certified for explosive atmospheres per PTB 06 ATEX 3001 Ex II (2) GD, making it suitable for installation in Zone 2 gas and Zone 22 dust areas when integrated into an appropriate enclosure. It withstands surge voltage of 6 kV and burst immunity of 2 kV on power ports and 1 kV on signal ports per IEC 61000-4-4, severity degree 3. Shock resistance is 15g / 11 ms. Relative humidity during operation may reach 100 %.
Mounting, clearances, and conductor terminations
Mounting is contactor-mounted in any position. Required clearances: 0 mm upwards, 0 mm forwards, 0 mm backwards, 0 mm downwards, and 6 mm at the side. Main current circuit terminals are screw-type accepting solid conductors 0.5... 4 mm², 2x (0.5... 2.5 mm²), or AWG 2x (18... 14). Dimensions: width 45 mm, height 64 mm, depth 73 mm. Power dissipation in hot operating state is 0.05 W total, 0.02 W per pole.