🔍 Key Concepts

• Net Positive Suction Head (NPSH) and how suction lift/head affect pump operation • How temperature affects water density and vapor pressure at the pump suction • What a water level control with probes does, and whether it changes actual pump suction conditions

💭 Think About

• Think about which condition would actually prevent water from reaching the pump impeller, causing loss of delivery, rather than just affecting controls or minor performance changes • Consider how too much resistance or pressure at the suction side versus too little lift would influence the pump’s ability to pull water into itself • Ask yourself which option deals with the physical hydraulics at the pump inlet, not the electrical or automatic control systems

✅ Before You Answer

• Identify which option changes the pressure at the pump suction enough to cause cavitation or starvation of the pump • Decide whether grounded probes would stop the pump mechanically from moving water, or just affect automatic level control logic • Compare what ‘low suction lift’ and ‘high suction head’ really mean in terms of ease or difficulty of getting water into the pump