A pump monitoring and notification system for a hydraulic pump includes an accelerometer and a controller. The accelerometer is associated with the hydraulic pump and is disposed relative to the hydraulic pump to generate acceleration data indicative of acceleration of the hydraulic pump. The controller is configured to access a fault threshold, access a time threshold, and determine an acceleration of the accelerometer based upon the acceleration data from the accelerometer. The controller is further configured to determine an RMS average of the acceleration of the accelerometer based upon the acceleration of the hydraulic pump, compare the RMS average of the acceleration of the accelerometer to the fault threshold, and generate an alert signal when the RMS average of the acceleration of the accelerometer exceeds the fault threshold for a time period exceeding the time threshold.

The present invention relates to a liquid feeding apparatus capable of feeding a liquid with high accuracy. The liquid feeding apparatus includes a liquid feeder having a downstream side, a plunger, and a cylinder that is configured for aspirating and discharging a solvent when a plunger slides. The liquid feeding apparatus further includes a pressure sensor for the solvent to be discharged, a selector valve configured to switch between a plurality of solvents to be aspirated and discharged, and a controller configured to control the liquid feeder and the selector valve. The controller controls the selector valve in synchronization with an aspiration operation of the plunger so that a mixing ratio of the solvents changes, controls the plunger to cause the plunger to operate at first and second accelerations that are different from each other, and suppresses a fluctuation of the solvent to be aspirated by the plunger.

A controller for operating a rod pumping unit at a pump speed. The controller includes a processor configured to operate a pump piston of the rod pumping unit at a first speed. The processor is further configured to determine a pump fillage level for a pump stroke based on a position signal and a load signal. The processor is further configured to reduce the pump speed to a second speed based on the pump fillage level for the pump stroke.