Siemens Circuit breaker, screw, size S0, 1NO + 1NC, 30 - 36A Part number 3RV2021-4PA15

Product Overview

The Siemens 3RV2021-4PA15 is a SIRIUS 3RV series motor-protection circuit-breaker (manual motor starter) in size S0. It combines overload and short-circuit protection, with an adjustable thermal release and a built-in auxiliary switch, making it a compact all-in-one solution for motor protection and control in industrial installations.

Key Features

• 3-pole motor protection circuit breaker (size S0)
• Adjustable overload current: 30 … 36 A
• Thermal overload release (Class 10) plus magnetic short-circuit release
• Integrated auxiliary switch (1 NO + 1 NC contacts)
• Rated operational voltage up to 690 V AC (20…690 V AC) / 50–60 Hz
• Screw-type terminals for main and auxiliary circuits; top and bottom connection possible
• DIN-rail mounting with screw + snap-on fixation for 35 mm standard rail
• Compact dimensions for space-efficient installation

Technical Specifications

• Article Number: 3RV2021-4PA15
• Product Family: SIRIUS 3RV motor-protection circuit breakers
• Poles (Main Circuit): 3 (3-pole)
• Overload Current Setting Range: 30 … 36 A
• Rated Operating Voltage (Ue): 20 … 690 V AC
• Rated Operational Current (Ie): 36 A (at AC-3, 400 V)
• Rated Motor Power (AC-3):
  • 230 V: 7.5 kW
  • 400 V: 18.5 kW
  • 500 V: 22 kW
  • 690 V: 30 kW
• Auxiliary Switch Contacts: 1 NO + 1 NC
• Auxiliary Contact Ratings (AC-15): 24 V: 2 A; 120–230 V: 0.5 A
• Auxiliary Contact Ratings (DC-13): 24 V: 1 A; 60 V: 0.15 A
• Short-Circuit Breaking Capacity (Icu):
  • 240 V AC: 100 kA
  • 400 V AC: 20 kA
  • 500 V AC: 6 kA
  • 690 V AC: 3 kA
• Short-Circuit Operational Breaking Capacity (Ics):
  • 240 V AC: 100 kA
  • 400 V AC: 10 kA
  • 500 V AC: 3 kA
  • 690 V AC: 2 kA
• Response Value (Magnetic Trip): 432 A
• Trip Class: Class 10 (thermal overload) + magnetic short-circuit
• Insulation Voltage (Ui): 690 V AC
• Impulse Withstand Voltage (Uimp): 6 kV
• Degree of Protection: IP20 (front, with terminals connected)
• Mounting Type: DIN rail 35 mm (screw + snap-on)
• Dimensions (approx.): Height: 97 mm, Width: 45 mm, Depth: 97 mm
• Net Weight (approx.): 0.425 kg
• Operating Ambient Temperature: –20 … +40 °C
• Storage / Transport Temperature: –50 … +80 °C

Compliance & Certifications

• Compliant with international motor-protection and circuit-breaker standards (e.g. IEC / EN standard series for low-voltage motor protection devices)
• Built-in auxiliary switch for control and signalling functions
• Designed for industrial, commercial and general motor-driven installations

Applications

The 3RV2021-4PA15 is ideal for protecting and controlling motors in industrial and commercial installations. Typical applications include motor protection for pumps, fans, compressors and conveyor systems, as well as integration into motor control panels and starter assemblies. Its adjustable overload setting and compact DIN-rail design make it suitable for a wide range of three-phase motor control tasks where both overload and short-circuit protection are required in a single device.