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More information in less space.       

It is amazing how sometimes similar applications can come back to back….Last week's blog came from a customer asking how to measure the main power grid frequency. And later the same week  I had a totally different customer ask me about how he could display upper, lower and current value of the main electrical grid frequency in groov. What are the chances of that!!??

This customer wanted one gadget to display all three values. Why so dense? Because they only use groov on smart phones, no PCs or Tablets. He was polling the data from a bank of UPSes and so needed to display a lot of data. Screen real estate is prime on those devices. What can we do to help?

In this week's blog, we are going to have some adventures in Z-Order.

Topics: Energy management, groov, Internet of Things, Remote monitoring, Tips, IoT, PACs, OEM, I/O

Of course you can include a trend in your PAC Display HMI or groov mobile operator interface and watch a value in your SNAP PAC System rise and fall over time. Or you can inspect a quick "plot" of it in PAC Control Pro's Debug mode.

But what if you just want to take a quick look at how high or how low an analog value has been, say, today?

This tip shows you how to do that using PAC Manager. 

Topics: Tips, optonews, PAC Project, OptoNews 2015-07-29

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50 or 60 Hertz - Roughly.

Measure the main power grid frequency, he said. It will be fun, he said…. Actually, pretty sure I said something like, “it will be easy”... and I was mostly right, and best of all, it did turn out to be fun!

It seemed like both a reasonable and easy request. The requirements were to measure the mains power grid frequency to a resolution of 0.01 Hertz, and to do it every 125 milliseconds (roughly; it could be a max of 200 milliseconds, but not much longer).

Why? In this case, the chase is better than the catch. It's enough to say the customer had his reasons, and this blog is about the chase.

Topics: Energy management, Process control, groov, Internet of Things, Remote monitoring, Electronics, Tips, IoT, OEM, I/O

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Loop the loop.

PID loops are used in a lot of different applications, and for good reason: they help keep our world under control. If you need to control a process temperature or pressure, you probably are going to use a PID loop. But are they always the right solution?

Ultra quick review; a proportional-integral-derivative control loop (or PID controller) compares a setpoint against a measured input value, and depending on the error, changes a control variable (output). It’s all about math. A PID loop is all about running a mathematical formula over and over at a specific rate.

The most common example of a PID loop that I often talk about in our monthly training class is the cruise control on a car. The speed of the car is the input, the accelerator is the output and the setpoint is what speed the car is doing the moment the driver presses the “set” button.

PID loops are so useful that sometimes we too quickly decide to use a one in a process when it may not be the best solution to the problem. In this week’s blog we are going to take a look at one instance where use of a PID loop may not be the best tool for the job.

Topics: Process control, PLCs, Remote monitoring, Tips, IoT, PACs, I/O

Suppose you need to monitor temperatures from several thermocouples wired to a SNAP-AITM-8 analog input module.

Or maybe you have a bunch of switches that are all wired to a high-density digital output module like the SNAP-ODC-32-SNK.

Here's a tip for anyone who needs to add several similar I/O points to a PAC Control strategy: you can save a lot of time by adding them automatically. 

Topics: Tips, Machine builder, optonews, OptoNews 2015-07-15, I/O

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Star Struck:

From a young age I have been looking up at night. Not sure exactly when I fell in love with astronomy, but I can recall looking up at the stars every chance I got as a kid.

I have ebbed and flowed with the amount of time and equipment I have had to spend on the hobby. In Australia I had a fully enclosed fiberglass domed observatory, which I chose to not ship over when my family moved to The States, but the desire to look up has not gone away.

Only the constellations at the horizon can be seen in both hemispheres, and even those look upside down compared to what I used to see. So I wanted to get something up and running fast here that would allow me some time to get my bearings in the sky and to share my new stars with my mates back in Australia via my personal website.

In this week's blog, I would like to share what astronomy tools I currently have set up, thanks to some Opto 22 hardware and groov.

Topics: Videos, Process control, Discrete control, groov, Internet of Things, Remote monitoring, Electronics, Tips, IoT, PACs

Accuracy and resolution both appear in specifications for our SNAP analog modules. But what do they mean, exactly? 

Accuracy

Let's start with accuracy, which is pretty easy to understand. Accuracy is how close a measured value is to reality, to the true quantity of what is being measured. 

Topics: Process control, Tips, optonews, OptoNews 2015-07-01

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Layers of security:

I wish there were, but there just isn’t.... There is no one device, hardware, or software that is the single defense for all known and future network attack vectors—including the one critical weakness: humans. You know, some thing or device that you could simply put at your network's front door and have it reject all the bad guys, but allow the friendlies in without question. Secure and easy is still a wish.

The solution then really comes down to layers. Adding layers that each will take a lot of time and a lot of effort to peel back, so much so that most attackers simply give up and move on.

The past few blog posts have talked about some of those layers, so let's now put it all together and see just how we might go about building a very robust mobile-accessible industrial automation network.

Topics: Process control, Discrete control, groov, Internet of Things, PLCs, Remote monitoring, Electronics, Tips, IoT, Machine builder, PACs, OEM, Integrators, Networking

Our tech tip this week comes from Philip in the OptoForum, who shared his PAC Control subroutine code for determining the time the sun rises and sets at a specific latitude. 

You could use HTTP requests over the Internet to get this data (discussed earlier in the same thread). But with this OptoScript code you don't need an Internet connection.

Topics: Tips, optonews, PACs, OptoNews 2015-06-17

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Two keys for secure communications:

What are SSL/TLS and HTTPS? You may have heard them being used on the Internet, and you have more than likely used them when logging into your bank, but what are they?

Is there anything you need to do to use these secure protocols?

What goes on "behind the curtain" in your web browser when you use them?

In this week's blog we are going to continue the theme of network security by taking a close look at SSL/TLS and HTTPS.

Topics: Discrete control, groov, Internet of Things, Remote monitoring, Electronics, Tips, IoT, Machine builder, Integrators, Networking