In relay pumping operations, as few as 2 engines can be hooked in series.

In relay pumping operations, as few as 2 engines can be hooked in series.

• A. 1 engine
• B. 2 engines
• C. 3 engines
• D. 4 engines

Answer: (B)

Relays pump by linking engines so the discharge from one engine feeds the suction of the next, building up the pressure (head) needed to push water farther or to a higher point. A relay can’t be formed with a single engine because there’s no downstream stage to continue moving the water. By bringing in another engine, the system becomes a relay and can achieve the extra head step by step. You can add more engines if you need even more pressure or distance, but the minimum setup to create a relay is more than one engine.

Relays pump by linking engines so the discharge from one engine feeds the suction of the next, building up the pressure (head) needed to push water farther or to a higher point. A relay can’t be formed with a single engine because there’s no downstream stage to continue moving the water. By bringing in another engine, the system becomes a relay and can achieve the extra head step by step. You can add more engines if you need even more pressure or distance, but the minimum setup to create a relay is more than one engine.