Jockey Pump Controller
The Pressure Manager

It Is Not a Fire Pump Controller

Unlike the fire pump controller, the jockey pump controller is a standard motor starter. It's typically a combination magnetic contactor and overload relay in a NEMA 1 or 4 enclosure, with two pressure-switch inputs (start and stop) wired to a small sensing line tapped off the system. It is not required to be listed for fire pump service, and it is allowed to trip on overload — the opposite rules from the fire pump controller.

Why the different rules? Because the jockey pump is not protecting life safety. If the jockey trips, the fire pump picks up slack. If the fire pump trips, the system fails. NFPA 20 reserves the strict locked-in-against-overload rules for devices whose failure would cause a sprinkler system to stop working.

Setpoints and Logic

Inside the enclosure are two pressure switches mounted on the pressure-sensing manifold:

• Start switch: closes contacts when pressure falls below the start set-point, energizing the contactor and starting the jockey motor.
• Stop switch: opens contacts when pressure rises to the stop set-point (typically 10 psi higher), de-energizing the contactor.

Some modern controllers use a single programmable transducer and electronic logic, but the mechanical two-switch arrangement is still common and field-serviceable with nothing more than a flathead screwdriver.

Troubleshooting

References