I had a borehole drilled almost 4 years back, but it was never a very strong hole. I could pump up to 1400 L and then I had to let it rest for at least 3 hours for the hole to fill up again before i could pump again. As time went by we realised that the time I could pump depended on the season and the ground water level.
In the summer I could pump for 35-40min but in the winter only for 25min max. I ended up using multiple automation’s for stopping and starting the borehole. I also have an level switch in series with the output of the Sonoff that can prevent the pump from starting when the tank is full. (Still need to wire the level switch back directly to the “Home Assistant” )
We also saw that with almost emptying the borehole with ever pump, that we had sand reaching the house filters ext, so we installed filters between the borehole and the storage tank. With time they block up and restrict the flow resulting in the tank not filling up in the allowed pumping time. This restriction can also cause a condition similar to a dry run condition and this is dangerous for the pump, so i had to rethink this control philosophy completely. I was also sitting with a condition where the sonoff would be on for 20 min every 3? hours without the pump running because the tank was full.
I then did the following:
I measured the current with an open pipe and saw that the motor draws 3.24Amps when moving the max water it can for the specific head in my installation.
I then started throttling the outlet pipe and recorded the current till the outlet was completely closed and recorded 2.56amps when the motor is moving no water at all.
I then used 3 automation’s in total to control the pump.
1: To start the pump, Three hours after it stopped.
2: To stop the pump as the hole starts emptying. (<2.8 amps)
3: To stop the Automation if the Start automation triggered a start while the tank is full. If this automation dont see current within 10 seconds after switching the sonoff on, it will switch the sonoff off again. (after 3 hours it will restart process and if there is space in the tank , the pump will continue running)
Benefit of new control:
1: Pump time will automatically follow seasonal changes in under ground water level.
2: Offer protection against Dry run conditions
3: Protect motor again overheating in the case of a blocked filter.
4: Prevent the sonoff from being on while the tank is full
- id: '1640943414758' alias: Borehole Level Stop description: '' trigger: - platform: numeric_state entity_id: sensor.borehole_current below: '2.8' condition: - condition: state entity_id: switch.borehole_sonoff state: 'on' action: - service: switch.turn_off target: entity_id: switch.borehole_sonoff mode: single - id: '1640950235654' alias: Borehole Start description: '' trigger: - platform: state entity_id: switch.borehole_sonoff from: 'on' to: 'off' for: hours: 3 minutes: 0 seconds: 0 milliseconds: 0 condition:  action: - service: switch.turn_on target: entity_id: switch.borehole_sonoff mode: single - id: '1640951248327' alias: Borehole Full Start Reset description: '' trigger: - platform: state entity_id: switch.borehole_sonoff from: 'off' to: 'on' for: hours: 0 minutes: 0 seconds: 10 milliseconds: 0 condition: - condition: not conditions: - condition: numeric_state entity_id: sensor.borehole_current above: '1' action: - service: switch.turn_off target: entity_id: switch.borehole_sonoff mode: single