13/04/2026
The Pumping Units
Electric Pump: The primary pump driven by an electric motor. This is usually the main "workhorse" of the system.
Jockey Pump: A much smaller pump designed to maintain constant pressure in the piping system. It prevents the main pumps from starting unnecessarily just to compensate for small leaks or pressure drops.
Valves and Control Components
OS&Y Gate Valve: Stands for "Outside Screw and Yoke." Its design allows you to see at a glance if the valve is open (stem is up) or closed (stem is down), which is critical for fire safety inspections.
Check Valve: A one-way valve that ensures water only flows in the correct direction and prevents backflow into the pumps.
Safety Valve: A relief valve that protects the system from over-pressurization by releasing water if the pressure exceeds a safe limit.
Pressure Switch: Sensors that detect pressure drops and signal the control panel to turn the pumps on or off.
Infrastructure and Support
Control Panel: The "brain" of the unit. The diagram mentions a PLC (Programmable Logic Controller) module, which automates the start/stop sequences and monitors for faults.
Fuel Tank: Likely connected to a diesel backup engine (not fully visible but implied by the tank) to ensure the system works even during a power outage.
Suction & Discharge: The Suction port is where water enters the system (usually from a tank or city main), and the Discharge port is where the pressurized water exits toward the building's fire protection system.
Strong Base: A heavy-duty steel frame that keeps all components aligned and allows the entire unit to be moved and installed as a single "skid."
