DIGITEN 4 Digital Green LED Tachometer RPM Speed Meter+Hall Proximity Switch Sensor NPN

Easy to fit. As others have mentioned the magnet is small and must be placed the correct way around. I glued it with a small dab of superglue. My maximum speed is 2000rpm so not expecting problems. At the specified 2-3mm distance it works fine with no erroneous readings. I had a 12V supply already available on the equipment and this worked ok. The settling/refresh time at reaching zero speed seems excessively long- but maybe it waits for this time to see if another pulse is coming - allowing it to read to very low speeds. Once rotating the reading is stable and refreshes regularly. For the price this is good value. Cannot comment on reliability as only just fitted but it appears robust. The application will run for several hours/day most days so will know more soon - will comment back in a few months if disappointed.

I’m very pleased with this...it’s been added to a metalworking lathe as attached photos. In order to keep things out of the way and clear of oil and swarf, the magnet is glued to the spinning knob at the rear of the headstock and the sensor is mounted in a wooden block underneath it, at an angle so that it’s roughly at right angles to the magnet face. The counter is also mounted at an angle in a wooden block, which allowed all the connections to be neatly inside. Both wooden blocks are held down with Velcro so that they can be removed and repositioned easily. Straightforward to fit...could be done simpler but I wanted it to be neat and out of the way. But it’s really good. I’m running mine off a 12v supply. A stronger magnet would allow the sensor to be placed further away...I did experiment but used the supplied one in the end because although I do have much stronger ones available, the supplied one did work at the required distance and it’s quite thin so doesn’t create much of a projection on the knob.I’m so pleased with this that I’ve just ordered another one as a spare! Recommended.Ps...as others have said, you need to get the magnet the right way up or it won’t work!

Worked perfectly for two years, but then unfortunately the display blanked.To be fair, the enviroment was not ideal as it was fitted in a boat engine room with some vibration and voltage up to the max allowed of 15v.I did check the unit was still powered OK.I’ll replace it with a similar unit, but perhaps stabilise the voltage to 12v in the hope of increasing reliability.

Works a treat and at a very reasonable price, tested against a calibrated optical tacho and within a couple of revs. Highly recommend

It is for spindle speed measurement of a lathe

Fitted to my new lathe at ~ £15, could not be better, quality is very good, works well and had easy to follow instructions. Longevity, unable to comment on, but hopefully will be ok. NOTE,, make sure you have the magnet right way up, if refers to this in the instructions.

This is good value. I fitted it on my milling machine and it works very well. The wiring diagram is clear and easy to follow. One thingthat is not mentioned in the instructions is that fact that the magnet has to be mounted the right way round, so check this beforemounting it permanently.

got this for my mini lathe and it works well, very good digital readout, but i had to put a stronger magnet on because the one that was supplied was not strong enough .