Dear Friend & Subscriber:
The desert is a perfectly agreeable place to live, so long as there's enough air conditioning and water for everybody.
But if the water pump dies, normally amicable, cheerful people get jumpy and irritable real fast. They can turn into outright Rednecks!
It's one thing to kick the cat when you're mad, but in the desert you may find yourself kicking other creatures. Like ferrets, snakes, coyotes, bats and porcupines.
Skirmishes with Mother Nature sometimes go very badly.
Our apps engineer got a solution request for just such a conflict, so today I'll describe a well monitoring application that prevents warfare with the critters squatting on your land, not to mention strife with your cousins who live in the trailer next door.
Plus this setup is perfect for farms and places where there's no cactus to be found anywhere.
A system like this normally has:
- A holding tank
- A pressure tank
- A pressure pump
- In-ground water pump
- Water meter
- Flow meter
When you can see levels and flow throughout the system, you know right away if anything is going haywire.
If you use wireless I/O to connect everything, all kinds of physical issues simply go away.
So here's the wireless pump monitoring system one of B&B's engineers, Bill Conley put together...
First, place a linear ultrasonic level sensor on the holding tank. This tells you how much water "inventory" the system has. A sensor with 4-20 ma output works great here.
Second, put a 0-100psig sensor on the pressure tank. This tells you how full the pressure tank is and how much water pressure is available in your trailer.
Add a current sensor on the power line to the pressure pump and another one on the in-ground water pump.
Also, add a flow meter that measures the flow into the holding tank or delivered to the trailer.
Now add up the I/O and pick the right Zlinx wireless I/O box for the application. Here we've got 4 analog inputs, 1 counter input and 2 digital outputs. We'll use the ZZ24D-NA-SR. If we ever want to add more inputs in the future, we can just snap on an I/O expansion module. Throw in a power supply and enclosure and bolt it to a post at the well-head.
Now for the magic. Half a mile away, back at the trailer, plug a Zlinx wireless modem into the modbus port of a little HMI. Bill wrote a little application for that HMI that displays tank pressure, volume and flow rate, along with high and low pressure alarms. Water and pressure pump current draws are displayed along with the amount of water delivered in gallons.
Zlinx modular wireless I/O
Zlinx industrial radio modems
If your cousins become envious of you and your reliable supply of water, they might break into your trailer and steal your pumping system and start playing Nintendo on your HMI. In anticipation of this, you will also want to buy some crime scene tape.
Total cost to keep your water flowing:
- HMI - $300
- Zlinx Radio Modem - $200
- Zlinx Wireless I/O - $400
- Power Supply and enclosure - $150
- Sensors - $400
Less than $1500 (crime scene tape not included). It's such a tidy little application that we'll write it up into an app note and maybe even kit it up as a quick and easy wireless solution. Let me know if you're interested and I'll keep you posted.
Now the Mrs. has all the water she needs for dishes, cooking and her Calgon baths. If coyotes start harassing us in our back-yard bar-b-que, I just spray them with the hose. The HMI says there's plenty of pressure available. That always give 'em a real big surprise.
Hey, who said rednecks couldn't live peacefully in the desert?
Don't forget the old bit of redneck wisdom that says the cleanest kid gets tossed in the tub first.