There are three general classes of position sensors that – taken together – form a position sensing hierarchy. This hierarchy applies to any underlying sensing technology, for example inductive, capacitive, ultrasonic, or photoelectric. Going from the most basic to the most advanced sensor operation, the hierarchy includes:
I received a call the other day from a customer who wanted to use a magnetic field sensor on a cylinder, and evidently was requiring very precise results. He asked, “what is the hysteresis of your sensors? I notice that it is listed in your catalog as a percentage and I need to know the exact value in millimeters.” My response was, “well it depends”, upon which he was not overly pleased. I then continued to explain my answer which leads me to the contents of this posting.
Paradigm shifts in automation are always occurring. The need for cost savings and higher diagnostics caused the shift from IP20 I/O to IP67 I/O. Now, we are in the midst of a shift to reduce or eliminate enclosures in industrial applications by removing control and power from the cabinet. With the reduction of IP20 I/O and enclosures, adding more I/O (discrete and analog) or specialty devices (RF identification, measurement devices, etc…) is now more difficult. In the past it was relatively easy, but expensive, to add another “slice” of I/O to an existing IP20 solution.
One of the things I am often asked about is “why use machine vision in packaging”? There are many reasons, including dealing with the perceived complexity of serviceability and cost. I will show you where the use of vision in packaging can significantly decrease a major cost factor called “planned downtime”, along with other benefits in this 3 part blog series – so stay tuned for my later posts.
In today’s competitive manufacturing environment, the name of the game is increased throughput. Unprecedented global competition means that industrial manufacturing machinery must be able to run better (faster, longer, hotter, etc.) and more reliably than ever before.
Written by: Jeff Himes
Selecting the correct inductive proximity sensor for an application can be an intimidating process. There are literally thousands of models available from various vendors so having a good starting point to narrow down the field is essential.
At this point is will be assumed that an Inductive Proximity Sensor is the type of sensor being selected. If you are at the beginning of your selection process, please read and earlier blog post pertaining to your initial sensor selection.
Every time I travel, customers tell me, “we just wire everything into a box.” Every equipment designer goes through a phase of their design process where they need to decide how their I/O gets from their sensors and their valves to their controller. Some people use I/O cards on their PLC, or networks with IP20 solutions inside remote I/O cabinets.
Written by: Bjoern Schaefer
The general sensing principle across this myriad of applications is nearly the same. As seen in last months post, the total amount of capacitance, as we remember, the ability to store a charge within an electrostatic field, depends on mainly three factors. Those factors are the ones which determine the success of your application.
The 2010 Windpower Expo & Conference in Dallas, held recently at the end of May, was a hotbed of technical and commercial activity this year. I had not attended the “Wind Show” since 2004, and I was amazed at the explosive growth of the event and overall industry in just six short years. This was a very substantial gathering, with about 1,400 exhibitors and 20,000 attendees.
There are better alternatives to detect pneumatic cylinder end of stroke position than reed switches or proximity switches. By better, I mean they are faster and easier to implement into your control system. In addition, you can realize other benefits such as commonality of spare sensors and lower long-term costs. So what are the better solutions?