Talk:Compressed Air Water Pump


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How deep of a well can the pump operate in? Can it operate in an 800 foot deep well?

Pump level sensing
The reference design has two probes to measure water level, which seems like an odd way to do this. You could as easily measure the level by the capacitance of an open-gap capacitor.

A potentially fun way to do this would be to have your 555 chip trigger based on voltage signals from the level sensor, rather than some internal capacitor.

For example, an AC adaptor could be tapped before the rectifier to give a 60Hz signal at a low voltage (5 or 12 volts,perhaps). This signal could be passed through the level sensor and resistor (using the sensor as a capacitor in a high-pass filter), and the signal across the resistor rectified and smoothed to give a voltage that changes with water level.

A scheme like that would allow the 555 timer to work with feedback from the pump itself, rather than simply feeding a signal forward.

Joel