In most industrial applications 80-90% of the I/O going back to the PLC is discrete points. Multiple times I have been asked, “How can I easily, quickly, and cost effectively get one channel of analog back to my PLC”. The solutions in the past have either involved an IP20 slice I/O solution in a J-box, which is expensive and labor intensive, or an IP67 network module, which reduces labor costs but still carries a high cost. A common drawback to these solutions is that you have to pay for 2, 4, or even 8 channels when only one is required.
Written by: Jeff Himes
I have led many inductive proximity sensor training classes where an “Ah ha” moment happens when discussing the effects of target size on an inductive proximity sensor. As more and more extended range sensing models arrive on the market, it’s even more critical to understand how target size affects sensing distance performance.
Did you know that you can improve your production and label quality by adding sensors to your process?
Here’s a brief overview of how sensors can help you:
– Anticipate roll change-outs to improve run time
– Verify label composition and placement, reducing product rejection
– Increase application reliability and detect jams automatically to reduce waste
Over the last year I have been discussing IP rated products with people in various positions in the manufacturing world and I have encountered some false assumptions about IP67 protection. I want to quickly go over what an IP67 test actually is and then go into the assumptions I’ve seen.
Applications involving precision motion control typically use electric servo systems for speed and accuracy, which electric servo systems can handle very well. However, in some cases, the accuracy delivered may be more than needed, and the cost of the electric servo may break the design budget. Fortunately, leading manufacturers of pneumatic valves are developing new high-speed control valves and sophisticated electronic controllers that allow incredible speed, precision, and variable load control to be delivered from a pneumatic cylinder. Most importantly, the overall cost of these servopneumatic systems can compare quite favorably with all-electric systems.
Pneumatic cylinders are used in many applications as prime movers in machinery, material handling, assembly, robotics, medical, and the list could go on. One of the challenges facing OEM’s integrators and end users is to detect reliably whether the cylinder has been fully extended or retracted before allowing machine movement. Solutions include the use of inductive sensors with some sort of target and internally mounted magnet (by the cylinder manufacturer) on the cylinder piston. In my previous blog, I discussed the two primary magnets, axially and radially magnetized magnets, used by cylinder manufacturers. Now, we will review one of the most commonly used magnetic field sensors to detect extension and retraction of the cylinder…the well-known reed switch.
Have you ever made the statement, “If I had it to do over again, I would’ve done it differently”? Well, here’s your chance. Many companies are migrating from DeviceNet to EtherNet/IP and now you can take this opportunity to do it differently. As a former Allen Bradley Instructor, I have seen enough bad DeviceNet installs to write a book. Here are six topics to consider in your new EtherNet/IP installations:
Linear position sensors are available with a variety of different output signal types to suit various application requirements and control architectures. Let’s take a look at three of the most common output signal types for linear position sensors; 1) analog, 2) time-based digital, and 3) serial digital, and discuss some of the pros and cons of each.
Written by: Jeff Himes
In almost all inductive proximity sensor applications the housing design and mounting method of the sensor need to be taken into consideration. Sensor housing designs have historically been described as shielded (sometimes called flush) or non-shielded (sometimes called non-flush). In reality the terms shielded and flush have different meanings just as non-shielded and non-flush have different meanings. By using these terms interchangeably some confusion is typically created. Additionally, a new term of “quasi-flush” has entered the market. Let’s take a closer look at these terms and what they really mean. Continue reading “Flush or Non-Flush, Looks Can Be Deceiving”