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

Ya es mi segunda compra

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.

Worked perfectly followed the instructions on Amazon for the wiring. Had to build a mounting bracket for the sensor, which was no problem. Mounted the magnet on the shaft and tested the tach would not work, flipped the magnet over work perfectly. Glued the magnet into place tested again and the tach worked great, so if it doesn’t work try flipping the magnet.

The media could not be loaded. This is a convenient device for providing speed readout on a machine tool. I printed a snug fitting collar for the end of the lathe spindle with a pocket for the magnet which was glued in place (be sure to check polarity first). A small box holds the board and display, a switch, and a 9V battery. The listing and photos have contradictory statements regarding voltage requirements, and the label stated 12-24V , but 8-24 seems to be correct. The device activates at a little over 8V. An aluminum bracket for holding the Hall sensor was attached to the back and that was it. The readings were accurate based in comparisons to a laser tachometer, and the display is fine and reasonably stable after a few seconds (the actual image is better than in the pictures because I just used a cell phone). Overall, this is a nice addition for 18 bucks.I subtracted one star because of the poor documentation. It is apparent from the reviews that many people found the hookup to be difficult. I believe it is actually very simple but needlessly confused by the bad description. One problem is that the connector wires are all white with red markings on the back to distinguish them. However, the photos show only the all white side. Since the plug can only be inserted one way, if the colored sensor wires connection to the labeled-side connector wires was shown in a single photo it probably would have eliminated all confusion. Anyway, several prior reviews have provided an accurate description of the hookup, and the Amazon description is also correct - just needlessly confusing.

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.