JacobSpringsFarm:Managewater

As of August 2016

The well water management system is designed to provide inexpensive monitoring of domestic and livestock water level in storage tanks and automatic control of the well pump to maintain water levels.

The Original System

Our well system is a little unusual, however the farmers who built the system did it this way to provide a few distinct advantages over traditional systems.

Instead of a typical on-demand pump feeding a pressure tank, in this system the well pump feeds a central pipeline that serves as both the feed line to fill the tanks and the supply line, based on gravity, from the tanks to the rest of the farm. The system allows continuous gravity-based water supply to the whole farm (including pressured sections if filters are removed) despite temporary power cuts and can be adapted with the addition of solar water pumping to provide a continuous off-grid water supply.

The Problem

The well control has no way of knowing when the water tanks are full to shut off. The tanks, located on the highest point of the property, are very far from a power source and it's not practical to run a control wire all the way there to monitor water level as wth a float switch.

Additionally, the pump control is not located anywhere near an unpressurized water one where a sensor could be installed to read water pressure and calculate when the tanks are full.

The Solution

It is built using a pair of Particle Photon chipsets which communicate with each other via the farms wifi network.

Archive

The first attempt at building a system failed for a multitude of reasons.

1. The sensor connection on the water tank was broken as it was strung through the feed-through (the hole was too small for the RS9 connector, so the connector was jammed through, but it broke some of the connections). 2. The water tank sensor ran out of batteries. Something was wrong with the solar-battery charging setup. 3. The code on the pump controller may or may not have had a fail-safe for hearing from the water tanks (will need to check). 4. We were using the wrong type of controller for the power control of the pump. We were using a 10A relay, when in fact we need a 2 hp contactor. To use a relay, it should be rated for 50A of resistive load. Anything less, and you risk fusing the relay in the 'open' position, leaving the pump on. This happens because of the large influx of current during the pump startup, which overheats the relay. This may have happened to the relay that was out there.

I found this out by <a href="http://electronics.stackexchange.com/questions/196976/relay-ratings-at-120v-and-240v-can-i-use-a-20a-240v-relay-with-a-13a-120v-pump">asking the internet</a>.

The new system uses Particle Photon WIFI devices, but we still need a contactor to switch on and off the pump. The code for the water tanks and pump control is tested and works, although the battery on the tank sensors seems to be dropping:

so I upped the sleep time from 10 mins to 20 mins, and we'll see how it does.

Here's a contactor for $25: http://www.ebay.com/itm/like/272008316055?ul_noapp=true&chn=ps&lpid=82

A new 50A SSR is about $50: http://www.newark.com/crydom/cwu2450p-10/ssr-panel-24-280vac-50a-screw/dp/72W3889.

Here's a live view of some of the data:

<iframe width="450" height="260" style="border: 1px solid #cccccc;" src="http://api.thingspeak.com/channels/62130/charts/5?width=450&height=260&results=1000&dynamic=true" ></iframe>

And the thingspeak channel with the data: https://thingspeak.com/channels/62130