Automatic thermal protection prevents motor burnout by disconnecting power if internal temperatures exceed safe operating limits

and terminal 6 is power closed

Rugged Durability: Stainless steel trim and ball prevent corrosion and ensure 0% leakage (Port A to AB) even in glycol-rich systems (up to 60%)

it ensures a seamless fit within the heater transition duct

Siemens Building Technology S55180-A157 Control 319847-401 Automatic thermal protection prevents motorThe Siemens Building Technology S55180 A157 is a heavy duty SSE Series electronic actuator engineered for precise 0 10V modulation in commercial HVAC systems. This 24VAC non spring return (NSR) unit is designed for normally closed (NC) operation, making it a reliable solution for modulating airflow or hydronic flow when paired with compatible 599 Series zone valves. With a 1 10 inch (2. 5 mm) stroke and a fast 12. 5 second positioning time, it