Belimo NRFA-S2 - rotary actuator for ball valves

Belimo NRFA-S2 – rotary actuator with fail-safe function

Actuator designed for ball valves. During operation, it moves the valve and tensions the return spring; if the power supply is interrupted, the spring moves the valve to the fail-safe position. For NC direction, this means the valve is closed (A–AB = 0%); for valves with an L-port, the data sheet specifies A–AB = 100%.

Key features and specifications

• Motor and fail-safe function torque: 10 Nm.
• Nominal voltage: AC 24...240 V / DC 24...125 V; frequency: 50/60 Hz.
• Close/Open control; motor running time: 75 s / 90°.
• Time to move to the fail-safe position: <20 s @ -20...50°C, <60 s @ -30°C.
• Auxiliary switches: 2x SPDT, 1x 10% / 1x 11...100%.
• Power consumption: 6 W while running and 2.5 W at rest; sizing value for cables: 9.5 VA.
• Power and control connection: 1 m cable, 2x 0.75 mm²; auxiliary switch connection: 1 m cable, 6x 0.75 mm².
• Mechanical position indicator, manual adjustment with a crank and position lock; rotation angle adjusted using mechanical stops.
• Protection rating: IP54; NEMA 2; UL Enclosure Type 2 housing.
• Ambient temperature: -30...50°C.