XBD-XBC Combined Electric Diesel Fire Pump Set for Fire Protection | Tengsheng

The XBD-XBC Combined Electric Diesel Fire Pump Set is a skid-mounted fire protection unit integrating an electric motor pump, a diesel engine pump and a jockey pump on a common base frame, designed for reliable water supply in fire protection systems. Its shared suction and discharge manifold arrangement provides automatic pump switching, backup redundancy and continuous pressure maintenance for building, commercial, industrial, and municipal fire protection applications.

 

With flow rates from 5 to 200 L/s and heads from 30 to 150 m, the set can be configured according to project-specific hydraulic requirements. The electric pump serves as the main duty pump, the diesel engine pump provides emergency backup on power failure, and the jockey pump maintains static pressure between operations; complete control panel, pressure gauges, gate valves and check valves are pre-installed and factory-tested for local fire code compliance.

 

Each pump set is performance tested before shipment, and technical documentation, dimensional drawings and selection support can be provided for project evaluation.

The combined fire pump set operates through an automatic pressure-based control logic managed by the central control panel. Under normal standby conditions, the jockey pump continuously monitors the system pressure via a pressure transmitter on the discharge manifold. When minor pressure drops occur from small leaks or limited demand, the jockey pump starts automatically to restore pressure, keeping the system charged without engaging the main pumps.

When a fire occurs or large flow is demanded, the system pressure drops to the first preset start threshold, and the electric motor fire pump starts automatically within 5 seconds, delivering the required flow and pressure through the discharge manifold to the fire risers, hydrants and sprinkler system. If the pressure continues to fall, the pump sequence control activates the next pump stage or switches to alternate operation to balance running hours.

If the electric pump fails to start, reaches its overload protection, or the main power supply is interrupted, the control panel immediately sends a start signal to the diesel engine pump, which starts within 10 seconds and takes over the fire protection duty. Once the fire is extinguished and demand ceases, the operator can manually stop the pumps; the system then returns to standby, and the jockey pump re-establishes normal static pressure. Pressure gauges, check valves and gate valves on each branch ensure one-way flow and allow individual pump isolation for maintenance without shutting down the entire system.

Extreme situation (mains power failure):

If the control cabinet receives a start signal but detects a loss of mains power, it will automatically start the diesel engine fire pump. The diesel engine pump reaches its rated speed within seconds and takes over as the main battle pump.
 

After extinguishing the fire:
Firefighters manually stop the main pump (electric or diesel engine) on site.
After the system pressure is restored, the stabilizing pump set automatically resumes operation, restoring the system to standby mode.