Modbus

If you were to look up “versatile” in the dictionary, you might find a picture of APG’s new MNU IS Intrinsically Safe Modbus Ultrasonic Sensor. Ok, you might not yet, but you should, and soon. With features like APG’s new QuickMode, global Class I, Division 1 hazardous location certification, and RS-485/Modbus RTU standard on every unit, the new MNU IS is capable of handling just about any level measurement situation. Let’s take a look.

There are so many communications standards out there: Modbus, Fieldbus, Profibus, Hart, and that’s just a few. You can get systems with HMI’s and PLC’s and RTU’s and… Yikes!

So how do you choose? What do they mean? “I just want to get the readings from my sensors!”

We hear you. We make several of our sensors Modbus-compatible, but we don’t do it for our sake, or even Modbus’s sake. We do it for you. So today, let’s take a look at what Modbus is, and why we use it.

The easiest comparison to make between the DCR-1006A Controller and the MND Modbus Display is that the DCR-1006A is generally specific, while the MND is specifically general. Makes complete sense, right?

One of the most frequently asked questions our Measurement Experts field is “How far away can my sensor be?” And the most popular answer we give is “What kind of signal does your sensor use?”

Because it really is as simple as that: the allowable distance between your sensor and control equipment is almost entirely dependent on the signal type your sends. There are, of course, other physical factors, like resistance and voltage, but the way they limit distance is different for each signal type.

So, how far can your signal go?

Ever wondered about sensor outputs? Why are there so many to choose from? Why not just standardize on one output, and be done?

Let’s take a quick look through the most popular types of sensor outputs. Each type has strengths and weaknesses that give it advantages in certain situations. Matching these qualities with your situation will help you maximize your sensors’ performance.

Not long ago, a major player in the commercial laundry and workforce uniform industry came to us with a few concerns dealing with their detergent and chemical tanks. They wanted to improve safety standards for their employees, and increase their efficiency with managing their chemical inventory. We knew we could help them do just that with our remote sensing solution.

The Concerns

In order to keep track of their chemical inventory, their employees had to climb on top of the tanks and look inside to make a visual evaluation of the liquid level.

Sometimes, the value of remote monitoring isn’t in how much you can do with it, but rather how little. There are many examples now of remote monitoring applications that are vast and complex. However, we’ve always been proud that our low cost solution provides similar sophistication for the little guy.

A clear example of this came in the form of a phone call, from a customer who didn’t need...