I need a simple system to switch a borehole pump on and off when the water levels are high and low in the tank. Preferably a 12v system (if possible) switching a 230v relay.

Ive got a float switch but it stops starts the pump as it only looks at about a 1/2 m of water level difference. I need one that switches on / off with about 1,5m difference as I have two 5000 l tanks installed with a 2,2 kw borehole pump.

Any suggestions will be welcome.

 

Two float switches? Bottom one switches it on, top one switches it off. Latching relay arrangement to finish it off.

See if you can find a pressure sensor. 

2 hours ago, Johandup said:

Ive got a float switch but it stops starts the pump as it only looks at about a 1/2 m of water level difference

I use only one like you. There is a weight on the wire (or suppose to be). You adjust its on/off distance by moving it towards or away from the ball. Play with it till you find the distance you want. If you dont have the time to play, @plonkster's plan will also work well. I prefer 2 float switches on bigger tanks like the 10000l and above.

 That yellow on the side is the weight:

Looking for a control like this

https://m.banggood.com/DF96D-AC220V-5A-Din-Rail-Mount-Float-Switch-Auto-Water-Level-Controller-with-3-Probes-p-1194872.html?gmcCountry=ZA&currency=ZAR&cur_warehouse=CN&createTmp=1&ID=241289&utm_source=googleshopping&utm_medium=cpc_union&utm_content=2zou&utm_campaign=ssc-za-all-0626&gclid=CjwKCAjwpuXpBRAAEiwAyRRPgeqLxHj16Rgpm3SIrTQCP16c_B54VgcTlLXCBcKK2qNt5DgQHalDDBoCs5EQAvD_BwE#popupStatedetail