In what situation cannot a jockey pump keep up with the pressure drop?

A jockey pump is designed to maintain the pressure in a fire protection system by making up for minor losses due to leaks or small demands. However, it has limitations based on the flow and pressure requirements.

Under fire flow conditions, the demand on the system increases significantly because the flow requirements are much higher to ensure adequate water supply for firefighting operations. This high demand can exceed the capacity of the jockey pump, which is not designed to handle substantial flow rates like those required during a full fire emergency. In such situations, the jockey pump cannot keep up with the sharp drop in pressure caused by the increased water flow required to fight the fire.

In scenarios like when the fire system is activated, during routine maintenance, or under non-operational conditions, the pressure dynamics can usually be managed by the jockey pump or the primary fire pump, as these situations do not typically impose the same level of demand on the water supply system as a full fire flow condition would.