High on the list of things you'd rather not do: clean up liquid waste from an overflowing storage tank.

Avoiding this kind of mess is especially good when your business includes storing and disposing of liquid waste from industry and manufacturing.

That's the business Plummer's Environmental Services is in.

Along with a variety of other services—including hydro excavating, manhole rehabilitation, and emergency spill response—the Michigan-based company collects liquid waste from Midwest industrial and municipal customers, stores it, and treats it.

Here's a tech tip for the more adventurous among you, who'd like to learn a faster, shorter way to code repetitious actions on similarly named variables or I/O.

A recent post on the OptoForum asked for an OptoScript equivalent to Eval(), a function used in a variety of programming languages, typically to act on expressions or operators passed in a string.

We won't get into the question of whether Eval() is "evil" or not (apparently it has a reputation for trouble in more than one language). Instead, we'll move right into how you can do good things by using a similar approach in your PAC Control strategy—and clean up a lot of spaghetti code in the process. 

You'll have three chances in the U.S. to explore industry trends and new products in the next few weeks.

One of those trends is mobile. Come see how you can monitor or control your automation systems and equipment with a simple groov mobile operator interface you build yourself—with no programming.

We'd be glad to see YOU at one of these three events: CSIA Executive Conference, Del Mar Electronics & Design Show, or The Automation Conference.

Monitoring the water mains:

As mentioned in my blog last week, it was not until I monitored my water usage that I found out I was not monitoring ALL of my water usage.

My whole house water meter was just that, the whole house. It did not show any of the garden/lawn water use.

Let's talk about how we might get that data and what it could mean for conserving water in all aspects of our lives.

The biggest user of water in our house is not human:

A web browser is installed on most of the key devices we use every day. PCs, smart phones, tablets, even our TVs now have a modern web browser installed. I can even surf the web from my Android smart watch (a Moto360).

It makes sense then, does it not, to view everyday data on an interface that we use every day?

How much water flows through our house was the subject of last week's blog... It both surprised me and pleased me to find out that the biggest user of water in our house was not a human.

Have you wondered if Opto 22 PACs and the PAC Project software suite would work for your application?

Or maybe you want to demonstrate the software to someone else—say, a customer or your boss. 

Here's a great free way to test it out: the PAC Project Demo, now with an additional demo screen and a small library of artwork pieces you can use any way you want to in your own HMI project. 

You've probably heard about the continuing drought in California.

The U.S. Drought Monitor at the University of Nebraska-Lincoln currently categorizes more than 94% of the state's total area as in "severe drought" or worse, and notes that snowpack statewide (from which we get most of our water through the year) is at only 5% of normal.

The worst-hit area is the center of the state, especially the Central Valley that produces many of the vegetables, fruits, and nuts that appear on dining tables throughout the U.S.—and the world.

If you're near Mobile, Alabama, or the Stennis Space Center in Mississippi, join us next week for the 3rd annual Allied Electronics Mobile Technology Day.

You'll see some 25 Allied suppliers at the Expo demonstrating the latest tech products and ready to answer your questions.

Be sure to look for Opto 22's Dan White. Dan will be there to show you how easy it is to build your own mobile app to monitor and control Modbus/TCP devices, OPC UA systems and equipment, and of course Opto 22 SNAP PAC controllers. 

Say you've got a dry contact switch you want to monitor so you know when it's closed. Could be a level sensor or pressure indicator, a magnetic reed switch or snap-action micro switch, or maybe a relay contact.

There are lots of ways you could do that, but often the best way is to use a SNAP-IDC5-SW digital input module. Why?

• It supplies 15 volts of power to an external dry contact switch.
• You only need 2 wires to connect the switch to the module.
• You can monitor 4 switches from 1 module.

Ben Orchard raves about this module in his recent blog post on monitoring water usage, and with good reason: it makes life easier by saving wiring time and complexity.

Visualizing water usage with groov:

As an Australian living in southern California I have been conflicted lots of times driving around seeing green lawns in baking hot sun.

When we moved to California from Australia in 2008, one of the worst droughts in history was still very much a huge issue for Victoria, the state we lived in. So when we arrived, the seemingly endless sea of green really, really surprised us all.

Australians have had little choice but to let their lawns brown off (often totally die) in the summer for many, many years...... It's just a fact of life of living in a sunburnt country.

As soon as we were able to buy our own home, I knew that monitoring our water usage was up near the top of my to-do list.

The challenge was how to share the data with the family, my wife and two teenage kids.