EEEkit 4 Digital Blue LED Tachometer, RPM Speed Meter with Hall Proximity Switch Sensor NPN, LED Panels Digital Module Digital Motor Tachometer for Quality Inspection Machines Conveyor Belts

Price is one of the best I found.No instructions are included, however the pictures on Amazon give a wiring diagram.. This is necessary because the "printing" on the case is almost too small to see.Plenty (actually more than enough) wire length is provided.Using this is quite valuable for me, the previous (from the factory) minimum speed was around 650 RPM, using this RPM indicator as a reference I was able to modify the speed drive to lower my minimum speed to near the 500 RPM I desired. Also I was able to see how fast this machine would go if the max speed stop is bypassed.The display can be mounted in a "project box" for a more professional appearance. (The current installation is temporary, and I haven't done this yet).The photos show my "temporary" installation". Demonstrating the device works as advertised. I assume it is accurate, although I do not have a standard to compare it to. RPM indications (in photos) show the limits of the machine (normal speed controls overridden to achieve top attainable speed).One slight negative, the display does not give "instant" response. Once speed changes it takes about a second to update. This isn't an issue but I felt obligated to point this fact out in the review.

I was not able to use the included Hall effect sensor due to space limitations, but I replaced it with a very small, flat one. Once wired, it works perfectly! This is a nice unit, and it makes my lathe much nicer.

This unit is easy to hook the sensor up. And easy to solder together. The tougher part is figuring out the wiring scenario. I use Google translate to help me with looking at the back of the LED module.1: + and brown wire of sensor2: ground3: blue sensor wire4: n/a5: black sensor wire12-24 volt power supply battery or transformer.The magnet provided will work, try flipping around and spinning on a drill to first check the sensor to determine what is the right direction. The South Pole is what the sensor will detect correctly.

Si piensas usar este medidor de RPM donde tienes un variador de frecuencia no gastes tu dinero, no filtra las señales que emite el variador por mas shield que le pongas.

I'll let my photo provide most of the details, but I am very frustrated to have wasted several hours trying to figure out this evidently defective device. In the course of testing it, I modified the cable, so cannot return. I'll be buying a competing product that has better documentation.The symptoms:After wiring the device, following the given instructions, the display remained dark and never showed digits when the Hall sensor was exposed to a varying magnetic signal. The polarity of the power supply and basic wiring was confirmed by the Hall sensor glowing and flickering in response to magnet motion. I then read more of the comments and saw that the number on the sticker were flipped. I rewired the unit to conform with the working configuration displayed in the youtube video "HOW TO WIRE DIGITAL TACHOMETER" cited in a comment. That's the final wiring layout in my image. I also tried flipping the magnet over as per another review, to no effect (except slightly lessening the sensor LED flicker).The fact that the wiring diagram and labeling on the case is suspect (see other reviews) should have tipped me off that this was not worth the money and time. It's outrageous that this kind of unit comes with no wiring specifications except the Amazon page! Give us a clue, please.

Took some fabricating to make a suitable bracket that wasn't in the way of anything but yet inline with a rotating ipulley. (half a day) Then extending the wires and running them to the dashboard area....... another couple of hours. Fired it up and all zeros. Getting frustrated. Moving the bracket, setting the pickup sensor closer to the moving pulley. Still nothing. Went back to Amazon and re-read some reviews. Sensor needs to be 5mm to 10mm away. OK.....got that. THEN I see one guys comment. "FLIP THE MAGNET OVER". Flipped the magnet and it works. Now I'll figure out where to mount the readout. But it does work. *Oh..... forget to mention that it never came with the little magnet. I ordered some from Amazon. I have like 20 of them now.Just incase one flies off. Bottom line. Well worth $18. But it's gonna be a process to mount it. I have one of those Japanese Mitsubishi MiniCab trucks. 660cc 3 cylinder engine that doesn't have a tachometer. This will be nice to assure me I don't over rev and blow the engine. Good luck.

Had to go back to the listing to find the wiring directions, and hooked up, worked just fine. Wires are a bit delicate so be gentle.

I tried using a small battery maintainer as my 12VDC power and got awful results. The tach showed all kinds of wrong readings; I think it must have been very electrically noisy. When I used a 12 VDC plugin adapter from an electronic device, the tach worked perfectly. The fact that there are no instructions packed with the device isn't helpful. The wiring diagram on the back of the display is correct as long as you view the wiring harness also from the back of the unit.

Ya es mi segunda compra