What causes excessive resistance on a fuel pump?
Incorrect connections will result in excessive resistance. Resistance results in heat and heat results in more resistance. A common issue we see is a result of poor fuel pump grounding running a eyelet from the pump ground to a rusty or painted surface. The resulting resistance can burn up fuel pumps, wiring and relays.
What is the total static head of a water pump?
The total dynamic head (TDH) is the sum of the total static head, total friction head and pressure head. The components of the total static head for a surface water and well water pumping system are shown. Total Static Head The total static head is the vertical distance the pump must lift the water.
What is the pressure of a center pivot system?
Center pivot systems require a certain pressure at the pivot point to distribute the water properly. The pressure head at any point where a pressure gauge is located can be converted from PSI to feet of head by multiplying by 2.31. For example, 20 PSI is equal to 20 times 2.31, or 46.2 feet of head.
What is the flow curve of a centrifugal pump?
A typical pump curve for a horizontal centrifugal pump. NPSH is the net positive suction head required by the pump, and TDSL is the total dynamic suction lift available (both at sea level). All pump curves are plotted with the flow rate on the horizontal axis and the TDH on the vertical axis.
What is the definition of a stalled hydraulic pump?
A stalled hydraulic pump is one the following: its outlet is blocked, to allow measurement of it maximum outlet pressure under stalled conditions a pump which has stopped delivering flow because of flow separation and cavitation on the impeller blade (s) Elon’s tweet refers to the second definition.
When does a motor stall what happens to the current?
Stalling is a condition at which a motor stops rotating even when there is sufficient voltage at its terminals. This condition occurs when the torque required by the load is more than the maximum torque (Breakdown torque) that can be generated by the motor. At this condition, the motor drains the maximum current and the speed comes zero.
How was the oil pump switched on after a stall?
To prevent the pump from running unnecessarily after a stall, a crash, or just sitting with the key on, the pumps were usually switched on by either the engine computer (through a relay), an oil pressure switch, or both (early GM systems especially).
How does a bi-directional variable displacement pump work?
The bi-directional, variable displacement pump controls the direction and speed of the hydraulic motor. This type of drive is commonly called a closed-loop system. Notice how the pump’s two ports are hydraulically connected to the two ports on the motor, forming the closed loop. Figure 1.