How to test a magnetic speed sensor (reed switch)

For more details visit www.chartered-engineer.com/

[@Pushrodgarage]

Thank you for pointing out the fact that I need a magnet to test my magnetic speed sensor.

[@charteredengineer]

You are welcome!

[@jessemorgan5508]

Thanks for this. Based on your instructions, I was able to test my sensor and find it was in the process of failing, but not dead yet. We've ordered a replacement, and in the meantime, we were able to shift the sensor closer to the pulley magnet to get the switch to close. Symptoms from the treadmill was erratic speed over several days before it refused to run completely. After unplugging, it would run for approximately 1-2 revolutions on the first attempt before shutting itself off because it was not getting signal from the sensor. (Nautilus t614.)

[@charteredengineer]

Well done Jesse - great work

[@jesussolis4833]

This man is a smart man. Thanks for the help.

[@charteredengineer]

Thanks for your kind words - I am only smart at some things!

[@kevinkeay5106]

Great video and explained in a simple way, thank you!

[@charteredengineer]

Thanks for the feedback!

[@nitinmishra540]

Really informative !

[@g00dl00kinb0i]

Great, I knew there was some way to test a magnetic sensor with a meter, nice video ! Now I just have to figure out how to apply this to an ABS sensor, only in my issue the sensor is the actual magnet that in the equation not the conductor.

[@kevinalexander2973]

Thanks for this info.

[@KianaShalix]

Thanks I will give this a try wish I saw this before I took out the motor and cleaned all them grooves in that Commutator (1hr later) cough lol.

[@tanhupseong6915]

Very informative

[@charteredengineer]

Thanks for the feedback👍

[@pancakesgo7995]

Thanks for the video. Is it common for the sensors to fail? My excercise bike is 9 years old and would intermittently not register RPM/speed, now it's packed up completely. I've had a fiddle with the sensor and cable, everything looks ok physically, but not had a multimeter on it yet.

[@charteredengineer]

Yes it is a common fault

[@muhammadababil9166]

Hello, can we use an iron logam instead of magnet?

[@josealvarez4130]

Hi very good videos I learned a lot.My daughter gave me a Nordictrack Treadmill C2300 model#NTL12905.0 the machine was working fine but when we move the machine with my son in law truck and we put it the power on, the consola buttons dosen't work only show SELECT USER 1 or USER 2.I check the speed sensor like you do and the motor and both work also I cleaned all the ribon cables and conector and still the buttons no working .What you recomende? Thank you very much

[@andrewgardner01]

Hi there, after some triaging found the magnet attached to our bike doesn't have any resistance as you show. Any idea where I can find an appropriate magnet? I can only make the sensor work at the moment when I put both ends actually touching magnets in the house (e.g. on cabinet doors)

[@turbofiat]

Thanks for your video. I've been struggling to build an electronic ignition system for my Trabant 601 (the car that's in my avatar). This engine uses two points and two coils (one set for each cylinder). It's a 2 cylinder 2 stroke engine. Looks kind of like a snowmobile engine. This same setup was commonly used on twin cylinder motorcycle engines. I had been using two of those points conversion systems but I am not having much luck. I bought a speed sensor for a Cummins Diesel I want to experiment with. After watching your video it appears that there are is no control module involved in the system? Like on an GM HEI system that uses a magnetic pickup, star trigger and a control module? So if I mounted this speed sensor in the ignition housing then connected one wire from the speed sensor to ground then the other wire to the negative side of the ignition coil, would that work? Or would I have to connect this speed sensor to some sort of control module? Based on your video looks like whenever the magnet approaches to the speed sensor all it does is complete the circuit like a set of breaker points/condensor. Or in other words it looks like a Reed switch. I have tested ignition coils by laying the coil wire on the engine block then connecting a wire to the negative side of the coil with the ignition on and tapped the wire to ground to check for spark. I once forgot to discharge the coil and when I grabbed the coil wire, I got a nasty shock! Thanks.

[@seciliasakaria4701]

I will create more magnetic switches using the same concept

[@g00dl00kinb0i]

Trabant 601 now that's a Soviet classic that moved the masses. I haven't seen one in decades, good luck with the project👍

[@reginasmith2933]

Do you get a voltage reading when your meter is set to alternating current?

[@g00dl00kinb0i]

It was set to continuity and the only voltage this would have would be a small residual charge from contact with skin at best. It's not an electromagnet.

[@JokerdanFF]

Good 👍

[@JokerdanFF]

Nice

[@ryanramlochan1504]

Good day can you do a video of a pull up and pull down hall effect speed or crank sensor,like bench test it just with a battery,sensor and a multimeter

[@charteredengineer]

Thanks for your suggestion. I will shoot a video for you....

[@ryanramlochan1504]

@@charteredengineer thanks

[@charteredengineer]

kzbin.info/www/bejne/j3eTYqGMnLiFnqs video for you Ryan!

[@RPWorks]

heloo. i have a 3 wire speed sensor on my bike. i modified the rear wheel and it has only two wire on the speed sensor. is it posible to connect it? 3 wires on my bike and 2 wires on my wheel ? how can i put the wire?

[@charteredengineer]

HI - probably not possible. A 2 wire sensor is most likely to be a magnetic reed switch and a 3 wire will be an optical sensor. The two are not compatible.

[@iupimen]

Hello, how do you test a senzor with 3 wire? Thanks

[@charteredengineer]

kzbin.info/www/bejne/j3eTYqGMnLiFnqs

[@rickfowler5342]

What if it's automotive and the magnet is actually IN the sensor?

[@charteredengineer]

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