Pepperl+Fuchs Blog

Ask an Expert Industrial Sensors - Episode 18

Posted by John Appleson on Fri, Jun 10, 2016

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:

1. Can NJ40+U4+W inductive proximity switches be run in series?
2. Does the NBB4-F1-E0 inductive sensor come in a different Hz to eliminate mutual interference?
3. Do you have beam benders for photoelectric sensors?
4. Looking for a Class I, Div.1 inductive sensor that does not need an IS barrier...
5. Do you have a wire-draw displacement sensor?
ask-an-expert-industrial-sensors-resized-600.jpgFeel 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: Zach, the first question asks about the voltage drop in a circuit. This customer installed four NJ40+U4+W inductive sensors and used a 3 amp fuse, 14 gauge wire, and the circuit is about 30 feet in length. He sends out 128 volts and only receives 106 volts back. He states that his load is a relay coil. Can you explain what is happening?
Zach: If you look at the data sheet for the NJ40+U4+W inductive sensor, you will see that it lists the voltage drop per sensor at about 5 volts. So if you have 4 sensors connected in series, you would expect to lose around 20 volts, which is what they are experiencing. The number of sensors that you can connect in series is limited by the voltage drop across each sensor, the supply voltage, and the operating voltage of the load.
John: This customer would like to know if the NBB4-F1-E0 inductive sensor comes in a different frequency to eliminate mutual interference. Zach, can you please share your thoughts on this?
Zach: One of the features of the F1 series inductive sensors is cross-talk immunity. This is only for the flush-mountable or shielded versions,  but you are able to order multiples of the same model without fear of mutual interference.
John: Zach, this customer has a thru-beam sensor, the SLA29/35/116R=65m, and he needs to change the direction of the beam to allow modification to a barrier safety system. What can you recommend here?
Zach: For this application we offer a deviation mirror designed for use with the single beam safety sensors. The model is SLA-1-M, and this will allow you to deflect the beam and cover multiple sides of an area with a single thru-beam pair.
John: This customer wants to know if we have an inductive proximity sensor that is suitable for Class I, Division 1.
Zach: We do offer one inductive sensor model that is UL and CSA approved for Class I, Div. 1 without the use of an intrinsic safety barrier. The model is 973EX4WI-A10T, and is an AC/DC sensor with a 30 mm diameter and 7 mm sensing range. It would still need to be wired in accordance to the guidelines set up for hazardous locations.
John: Here's a unique question-this customer would like to know if we have a wire-draw displacement sensor. If yes, what is the model? If not, what are other options?
Zach: Our option for wire-draw displacement would be a combination of two products: A rotary encoder paired with a cable pull. The cable pull accessory can be used with any encoder models that feature a 58 mm diameter housing, but there are some exceptions, such as the 36 mm analog encoders, which can also be used. The encoders are a solid shaft style and there are cable pull models for either a 6 mm or 10 mm shaft size. Even the cable pull wire is available in various lengths, so he can configure a solution for any wire-draw displacement application.
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.
Questions about Industrial Sensors?  Get the Quick Select Product Guide

Topics: Rotary Encoders, Inductive Sensors, Photoelectric Sensors, Ask an Expert

Subscribe to Our Blog

Stay current on cutting-edge industrial automation technology and applications.

Subscribe to Our Blog


Recent Posts

Search our blog!

Loading Google Custom Search.....

Posts by Topic

see all

Follow Me