Siemens 3RN2010-1CA30 Thermistor Motor Protection Relay 24V AC/DC

The Siemens 3RN2010-1CA30 is a SIRIUS 3RN2 thermistor motor protection relay in compact evaluation unit design, suitable for bimetallic switch sensors. It operates on a 24V AC/DC supply with automatic RESET and provides 1 NO and 1 NC output contacts with galvanic isolation between input and output circuits. The 17.5 mm wide device mounts on a standard 35 mm DIN rail via screw or snap-on fixing.

Technical specifications:

• MLFB: 3RN2010-1CA30
• Manufacturer: Siemens
• Product line: SIRIUS
• Supply voltage Us: 24V AC (50/60 Hz) / 24V DC; operating range 0.85...1.1 x Us
• Output contacts: 1 NO + 1 NC
• Thermal current (contacts): 5 A max
• Operational current: 3 A at AC-15, 250V / 1 A at DC-13, 24V
• Fuse link rating: 6 A (DIAZED, continuous)
• Insulation voltage: 300V (OVC III, pollution degree 3)
• Surge voltage resistance: 4 kV
• Power loss: 0.4 W
• Contact material: AgSnO2
• Terminals: Screw type, removable; 0.5...4 mm² solid/stranded
• Mounting: 35 mm DIN rail, screw or snap-on
• Dimensions (WxHxD): 17.5 x 100 x 90 mm
• Weight: 127 g
• Operating temperature: -25...+60°C
• Storage/transport temperature: -40...+85°C
• Relative humidity (operation): max 70%
• Installation altitude: max 2,000 m
• Mechanical service life: 10,000,000 operating cycles
• Electrical endurance: 100,000 cycles (AC-15)

Features and benefits:

• Automatic RESET returns the relay after fault clearance without manual intervention
• Galvanic isolation between thermistor input and output contacts ensures safe circuit separation
• Min 40 ms power-failure buffering maintains relay state during brief supply interruptions
• Two LED indicators (Ready/Tripped) give immediate visual fault status on the front face
• Zero required side-by-side spacing enables compact DIN rail panel layouts

Applications:

• Overtemperature protection of AC motor windings via thermistor or bimetallic switch sensors
• Motor control panels requiring electrical separation between sensor and output circuits
• DIN rail assemblies in industrial switchgear and control cabinets
• Drive systems where automatic fault RESET reduces maintenance downtime

Compliant with IEC 60664 (insulation coordination), IEC 60068-2-27 (shock resistance), IEC 60068-2-6 (vibration), IEC 61000-4-4 (burst), IEC 61000-4-5 (surge), and IEC 61000-4-2 (ESD). Part of the Siemens SIRIUS 3RN2 range.

Also known as: Siemens 3RN2010-1CA30, SIRIUS 3RN2 thermistor relay, Siemens thermistor motor protection relay 24V.