Siemens 3RU21264BB0 14-20A Thermal Overload Relay

Siemens 3RU21264BB0 14-20A Thermal Overload Relay

A compact, reliable protection device for three‑phase electric motors. Designed for Siemens SIRIUS 3RT contactors (Size S0), it shuts off the motor if current exceeds safe limits or a phase fails. It can be reset manually or automatically.

Key Features

• Adjustable current range: 14 A to 20 A

• Trip class: Class 10 – trips in about 10 seconds if overloaded 

• Mounting style: Direct mounting onto Siemens 3RT Size S0 contactors, using screw terminals

• Reset options: Manual or automatic reset, with TEST and STOP buttons and a trip-status indicator

Specifications

• Rated voltage: Up to 690 VAC, 50/60 Hz

• Operating temperature: –20 °C to +70 °C (storage down to –55 °C)

• Protection rating: IP20 (finger-safe front)

• Poles: 3-pole design for three‑phase protection

• Dimensions: Approximately 85 × 45 × 85 mm, weighing about 0.43 lb (0.19 kg)