What component energizes and deenergizes the pump to control the hotwell level?

What component energizes and deenergizes the pump to control the hotwell level?

• A. Float Switch
• B. Pressure Switch
• C. Thermocouple
• D. Control Relay

Answer: (A)

The function here is level sensing that directly drives the pump. A float switch uses a buoyant float attached to a switch; as the hotwell level rises, the float lifts and closes contacts, energizing the pump to remove water. When the level drops to a lower point, the switch opens and the pump turns off. This on/off action keeps the hotwell within its desired range, often with a bit of hysteresis to prevent rapid cycling. A pressure switch would react to pressure rather than level, a thermocouple measures temperature, and a control relay by itself isn’t a level sensor—it needs a sensing device like a float switch to actually energize or deenergize the pump.

The function here is level sensing that directly drives the pump. A float switch uses a buoyant float attached to a switch; as the hotwell level rises, the float lifts and closes contacts, energizing the pump to remove water. When the level drops to a lower point, the switch opens and the pump turns off. This on/off action keeps the hotwell within its desired range, often with a bit of hysteresis to prevent rapid cycling.

A pressure switch would react to pressure rather than level, a thermocouple measures temperature, and a control relay by itself isn’t a level sensor—it needs a sensing device like a float switch to actually energize or deenergize the pump.