This episode of Ask an Expert for industrial sensors examines and provides answers to interesting sensing questions we've received from customers just like you. We explore and answer these questions:
- How to best tackle clear object detection
- How much pressure can be applied to a sensor before you determine that maybe that wasn't such a good idea
- Caustic environments that can damage sensors
- Valve sensors
Feel free to ask us your sensing questions, and we'll do our best to reply with the whys and hows of a particular solution.
John: Welcome to Ask an Expert! Hi, this is John Appleson, Marketing Manager with Pepperl+Fuchs. Today I'm joined by Zach Steck. Zach works as an application engineer here at Pepperl+Fuchs. So welcome Zach, and thanks for being here!
Zach: Hi John, thanks for asking me
John: Ok, the first question asks about a retroreflective photoelectric sensor, the ML71 Series (ML71-6/59/102-115). A company is using this sensor to pick up labels on a stacker, and they're having issues with detecting clear material, and then the gaps in between that material. Zach, is the ML71 Series suitable for use in this application?
Zach: This ML71 sensor would not be suitable for detection of transparent objects. In our model number nomenclature we identify a retroreflective sensor with clear object detection using a -G in its model number. Since this model does not contain a -G, we would have to suggest an alternative for this application. The ML7 Series would be our most similar, featuring clear object detection.
John: Here's a question about an application where they are using a UB500 ultrasonic sensor (UB500-18GM75-I-V15). This sensor is being used for position feedback, and needs to be subjected to one megapascal pressure. Zach, can this sensor withstand that kind of pressure?
Zach: In general, we do not recommend using an ultrasonic sensor in any application where it is exposed to pressure. Pressure puts stress on the sensor transducer, and can greatly reduce the life of the sensor. In this case, one megapascal is about 145 PSI, which is way too high for an ultrasonic sensor to function properly. This much pressure would weigh down the transducer, making the sensor completely unusable. A common solution for level indication on high-pressure tanks is a sight glass paired with capacitive proximity sensors.
John: Here's another ultrasonic sensor question. This customer needs to measure the levels of caustic soda at a temperature of 85 °C. Can you recommend the UC10000 sensor (UC10000-F260-IE8R2) for this application?
Zach: There are a couple of reasons why I would not suggest this sensor based on the application description. My biggest concern is the temperature. This sensor is only rated for a maximum operating temperature of 70 °C, so you would not want to install it in an area where it is constantly exposed to 85 °C. Another concern would be the highly corrosive nature of the caustic soda. With this mixture, you would want to use a chemical resistant ultrasonic sensor, such as our UCC Series, that features a stainless steel housing and PTFE coated transducer.
John: Zach, another customer needs to find an open/closed sensor for a manual gate valve. Do we offer such sensors?
Zach: We do not offer any sensors that are specifically designed to work with this type of valve, so their best option would be a couple of cylindrical inductive sensors mounted in a way to determine the open or closed position of the valve.
John: Well that concludes this segment of Ask an Expert. I'd like to thank Zach for joining me today and thank our audience as well!