Frequently Asked Questions
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How do magnetic sensors work? |
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They either have an internal magnet, or an external magnet. The internal magnet sensors detect ferrous steel, and produce either analog or digital output. The external magnet sensors detect the magnetic field from a magnet or electro coil. They also come in analog and digital versions. Step 1 of the Sensor Selection Wizard breaks our product line into different "types" of magnetic sensors. |
What is the best way to find the magnetic sensor I need? |
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Click the Products link at the top of this screen. Then click the Sensor Selection Wizard box. This is a 5 click process. Click the picture that best describes your needs to go to the next step. If you don't know which picture to click, the 1st box is the most common option, or call us at 970-879-9900. |
What is the farthest a magnetic sensor can see? |
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For '0' speed detection and power up recognition, our EPPHS Either Pole Programmable Hall Switch can trigger on 2 gauss. Our RM-01-038 magnet (.87" diameter)produces this at about 6". For non-zero speed movement, we have an AC coupled GMR sensor that can see magnets up to a foot away. |
How do I order your magnetic sensors and sensor accessories? |
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We take orders by calling 970 879-9900 x300. We can take a credit card (Visa, MasterCard, AMEX), or PO after setting up an account. |
Is Sensor Solutions ISO or QS Certified? |
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Sensor Solutions is certified to the ISO 9001:2008 quality standard. |
Are your sensors CE certified? |
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Although CE marking is not standard, a majority of Sensor Solutions sensors can be CE marked for a nominal charge. Contact Sales for details. |
How do I get parts that will pass my CE testing? |
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Email engineering from the link at the bottom of the page. We are working on adding 'CE' options to our catalog selection. |
Do you have RoHS Compliant magnetic sensors? |
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Most of our customers use the RoHS directive exemption under Category 9, products for monitoring and control. We now offer RoHS products on a custom basis, contact us for further info. |
Why aren't all of your products RoHS compliant? |
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Lead is the only item of concern. Lead free soldering is more expensive and not as reliable as conventional soldering. We now offer RoHS sensors on a custom basis. If you require RoHS compliant sensors, contact us via phone or email. |
Can you provide replacements for obsolete Airpax and Electro Corp sensors and pickups? |
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We have designed exact replacements and can also provide sensors from our catalog with the same outputs and thread types. Check our Cross Reference page to see if we list a replacement, if not contact Engineering via phone or email to discuss the options. |
Can you cross reference other manufacturer's part numbers? |
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Lots of times we can provide a direct replacement. Click the Cross Reference link above or call us for info. |
How do I get applications support? |
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Either call us, or at the bottom of any page, there is a blue hot link 'Email Engineering'. Click this hot link. Make sure to fill in the proper e-mail address for the reply. |
Is your product pricing published on line? |
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For most of our sensors, yes. Use the sensor selection wizard to get to the product page. After choosing the connection (step 5 of 5), you can see & print a photo of your selection, view pricing, and have the option to download the pdf data sheet. |
How do I determine the north and south poles of a magnet? |
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This is a confusing question, with conflicting answers listed across the Internet. The following methods will indicate the poles as defined within the magnetic sensing industry.
1.) Use a compass: The south pole of a magnet will attract the end of the compass needle pointing north.
2.) Float the magnet in still water, the north pole of the magnet will align with magnetic north.
3.) Opposites attract, use a magnet with known poles, the marked north will attract the south pole of the unknown magnet.
4.) Purchase your magnets from Sensor Solutions, the south pole is labeled on the magnet or defined on the specifications sheet for potted magnets. |
How do I buy product from outside the US? |
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We ship FOB Colorado, USA around the world using UPS. We can take a credit card, or wire transfer directly into our account. |
I'm not sure what target to detect. |
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Every sensor needs something to 'detect'. Hall switches detect a magnet. Magnetic proximity sensors detect ferrous steel. Gear tooth sensors detect gear teeth, holes, or other ferrous targets. Our targets can be found by clicking 'Products' above and then select raw magnets, potted magnets, gears, or shaft collars to see our current selection. |
What is the effect of Chopper Stabilization? |
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Chopper stabilization corrects for the magnetic offset and allows our sensors to be made more sensitive. From the customer's perspective, a chopper stabilized sensor will trigger on slightly after the magnetic field. This uncertainty will be from 0 to 1 / Chopper Frequency. Typically this is less than 16uS. |
What is the best way to measure speed from a magnetic gear tooth sensor? |
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There are 2 ways to measure speed from the continuous pulses produced from gear teeth: count the number of sensor pulses in a fixed period of time, and count the time between each sensor pulse. If you count the number of pulses, make sure you are counting at least 20 pulses at your maximum speed. If you are measuring time between pulses, make sure to use the same edge (rising or falling), and note that the chopper stabilized sensors will have tooth to tooth uncertainty of up to 1 / the chopper frequency. Typically this is 16uS. Never try to measure the time from rising edge to falling edge for speed. |
What does a quadrature gear tooth sensor do for me? |
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A quadrature sensor can give you direction information, and can increase the measuring system's resolution to 4 times the number of targets. It produces 2 square wave outputs, Ch A and Ch B. So, you get 4 'edges' from each tooth or target: Ch A rising and falling, Ch B rising and falling. In one direction of movement A leads B. In the other direction, B leads A. If a system has a tooth-to-tooth spacing of .100", each 'edge' is approximately .025" apart. |
What is the best way to measure speed from a quadrature gear tooth sensor? |
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A quadrature gear tooth sensor has 4 edges, Ch A rising, Ch B rising, Ch A falling and Ch B falling. Gear tooth sensors never have exactly 50.0% duty cycle signals, and the phase angle is never exactly 90.0 degrees. Therefore, the time between these 4 edges is not exactly the same. To measure speed, look time between the same edges; for example Ch A falling to the next Ch A falling. Note the non-chopper stabilized sensors have less tooth to tooth 'chatter' caused by the chopper frequency. |
Do you make sensors other than what is listed on your web site? |
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Yes. We have several other 'application specific' sensors that are not listed. Contact Engineering to see if we can make a sensor for your application. |
Where are your products manufactured? |
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We use components manufactured across the globe. All final assembly and testing is done in Steamboat Springs, CO, USA. |
Can your sensors survive a radioactive environment? |
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Yes, we have built custom magnetic sensors that have traveled down the core of a Nuclear Reactor. |
Is there a list of applications notes? |
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We have quite a few applications notes but have not had a chance to add them to our web site. Contact Engineering using the Email Engineering hot link at the bottom of any page, or call 970 879-9900 x 302. |
Do you offer complete systems, including the meter, cable and sensor? |
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Yes. Click the Products link at the top of any Page. Scroll down to the 'Tachs, Meters & Controllers' and click the picture. We have several systems that are not listed, contact Engineering with your application. |
I don't have a gear that I can detect; how can I get speed information? |
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You can detect a steel bolt head or a hole in a steel target with a Gear Tooth Sensor or a Ferrous Metal Detection Sensor. Otherwise, you can attach a magnet to the rotating target and detect it with a Hall Switch. We provide raw magnets, magnets potted into threaded bolts, and magnets mounted on shaft collars. Click on the "Products" link above to see our target options. |
What is the difference between 0 SPEED, TRUE 0 SPEED, and VERY LOW SPEED sensors? |
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True 0 Speed means if you start today and one target passes the sensor in the next year, the sensor produces an appropriate pulse. Very Low Speed means the targets can pass by at less than 1 target per second, and the sensor works. Some competitors claim 0 speed on their Very Low Speed Sensors even though they don't work to true 0 speed. |
What is the difference between the Single Channel Gear Tooth Sensor and the Single Channel Target Tracker Gear Tooth Sensor? |
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Several things. The Single Channel DS is true 0 speed, chopper stabilized, requires direction of rotation orientation, and looks for target left vs. target right. The Target Tracker DSO works to very slow speeds, does not have chopper noise, and does not require orientation. It is sensitive to metal close and metal far. |
Which gear tooth sensor should I use, The Gear Tooth Sensor or the Target Tracker? |
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It depends on your requirements. In general, use the DS Gear Tooth Sensor if you have a standard gear, and a Target Tracker DSO if you can't orient the sensor to the gear or want to produce pulses that track the teeth pattern. The DS sensor behaves more consistently from part to part, but if you gap them close enough the DSO sensors work great. |
For a Quadrature or Speed Direction Sensor, when should I use the DSO 'Target Tracker' instead of the DS gear tooth sensor? |
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If the gear you are sensing has teeth that are longer than .250" at the outside diameter, or the teeth are farther apart than .650" at the outside diameter, use the Target Tracker DSO. |
How can I detect the speed and/or the direction of a rotating shaft? |
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One option is to mount magnets directly to your shaft. Another option is a shaft collar containing magnets that can be attached to the shaft. These targets can then be paired with a Hall Effect sensor to give you the outputs you need. We provide a variety of target options and can also create custom solutions as required by customers. |
