In typical sensors all you get is ON or OFF… we just hope and assume that the prox is working, until something doesn’t work properly. The part is seated but the sensor doesn’t fire or the operator can’t get their machine to cycle. This can sometimes be tricky to troubleshoot and usually causes unplanned interruptions in production while the maintenance teams attempt to replace the sensor. On some recent customer visits on the east coast, I have had a number of interesting conversations about the customer’s need to collect more information from their sensors; specifically questions like:
- How do I know the sensor is working?
- How do I predict sensor failure?
- How do I know something has changed in the sensor application?
- How do I get my sensor to provide adaptive feedback?
- How do I plan preventative maintenance?
- How can I increase the overall equipment throughput?
- How can I increase my process reliability?
Continue reading “3 Production Problems Solved by Intelligent Sensors”
Honestly, every day we run into one of the most commonly seen and vital categories of automation equipment imaginable on the factory floor – the good old automation stalwart servant, the feeder bowl.
These devices are imperative to successful automated assembly processes and are used in hundreds of applications in factory automation. But the successful and timely, synchronous delivery and individual of components provided by the feeder bowl from the bowl itself through the feed track system, is dependent on reliable sensing. If “clogs” or traffic jams occur anywhere in the pathway, it interferes with the overall timely assembly of goods, regardless of the industrial discipline. We see a wide array of sensing technologies from manufacturer to manufacturer, regardless of the country of origin, regarding sensing in these machines.
Inductive proximity sensors, ultrasonic sensors, photoelectric types are all integrated into the tracking of screws, nuts, washers, and a wide array of other metallic and non-metallic sub components fed into the manufacturing stream. One of the most common products used in sensing components being supplied through feeder bowl tracks even today, is the separate amplifier and armor jacketed pair of fiber optic emitters/receivers. Do they work? Absolutely. Do they fail? Absolutely.
Continue reading “I’ve got the Feeder Bowl Blues (not to be confused with “Feed Bag Blues”)”
It’s another day at the plant, and the “Underside Clamp Retracted” sensor on Station 29, Op 30 is acting up again. Seems to be intermittently functioning…the operator says that the line is stopping due to “Error: Underside Clamp Not Retracted”.
You think to yourself, “Didn’t we just replace that prox last week?” A quick check of the maintenance log confirms it: that prox was indeed replaced last week. In fact, that particular prox has been replaced seven times in the last six months. Hmm….the frequency of replacement looks like it’s going up…four of the seven replacements were performed in the last two months.
What’s going on here? Is it really possible that seven defective proxes just all happened to end up at Station 29, Op 30, Underside Clamp Retract? Not likely!
Continue reading “Broken sensors that won’t stay fixed!”
In a previous blog Flush or Non-Flush, Looks Can Be Deceiving, Jeff mentions the two common housing designs of inductive sensors, flush and non-flush. So what does this mean to you when you are applying an inductive or even a capacitive sensor?
Flush-style sensors actually have a shield that restricts the magnetic field so that it only radiates out of the face of the sensor. Flush-style, or shielded sensors, can be mounted flush in a metal bracket or even in your machine without the metal causing the sensor to false trigger. When mounting two shielded inductive proximity sensors next to each other, you should typically leave one diameter of the sensor between adjacent sensors. The shielded-style of sensor will typically have approximately one-half of the sensing distance that a non-shielded version will have. For example, a 12mm shielded inductive sensor will have a sensing distance 2mm whereas a non-shielded version will have a sensing distance of 4mm. Although shielded style sensors have a shorter sensing range they can be buried in a machine or a bracket that will offer protection against damage.
Continue reading “Flush or Non-Flush – What’s the Difference?”
I am experiencing the future of tradeshows; a networking & educational conference without the travel, the expense, and the suit! I can sit at my desk and make contact with future vendors and customers. The online database GlobalSpec hosts multiple times per year industry specific virtual tradeshow events. There are presentations and exhibitors. A place to sit and drink virtual coffee with your peers and of course the token giveaway raffles.
Today I am working the Balluff booth in the Sensors and Switches Virtual show. It is a collection of companies and attendees from many different industries. I really enjoy these events because we can contact quickly with potential customers and potential vendors right from the comfort of our conference room and at a much reduced cost. Here you can see our hard working staff chatting with customers.
Check out the Balluff booth at the Sensors & Switches Virtual Tradeshow, it will be available to visit for 90 days from today.
Written by: Jeff Himes
An inductive proximity sensor is a non-contact device that is used to detect a metal target. When power is applied to an inductive proximity sensor the sensor’s coil will generate an oscillating electromagnetic field out of the face of the sensor. This field will vary in shape and size depending on the diameter of the sensor and whether the sensor is a shielded or non-shielded model. For example, a M12 size sensor will generate a smaller electromagnetic field than an M30 size sensor. When the metal target gets close enough to the sensor’s face it begins to penetrate the electromagnetic field. When this happens, eddy currents are generated on the surface of the metal target. As the metal target gets closer to the sensor face – the eddy currents increase – which in turn decrease the amplitude of the electromagnetic field. Once the electromagnetic field’s amplitude is reduced to a certain level – the sensor will activate indicating it has detected the metal target.
This explanation is a little wordy and, as in most cases, a visual demonstration can be of great help. Watch this short video explaining the basic functionality of an inductive proximity sensor.
For more information on inductive proximity sensors, click here.
Written by: Jeff Himes
An inductive proximity sensor is meant to be a non-contact device. If contact is made with the face of the sensor by its metal target – it will typically fail. What if you want the reliability of an inductive proximity sensor – yet you want physical contact with the device too? Is this really possible? Yes – by using a mechanical device I call a Banking Screw.
Continue reading “Mechanical Probe Eliminates Impact for Inductive Proximity Sensor”
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.
Continue reading “Does target size affect the sensing performance of an inductive proximity sensor?”