AstroAI Digital Multimeter, TRMS 4000 Counts Volt Meter (Manual and Auto Ranging); Measures Voltage Tester, Current, Resistance, Continuity, Frequency; Tests Diodes, Temperature (Red)

Great multimeter, works great and seems to have good quality.

I use it almost every day, to see if I am still alive....kidding. Just a great meter. I use it on the boats (nightmare), electronics, vehicles etc. Had it for years and if you turn it off the batteries will last a long time. This is not like a brain surgery review. Volt Amp meters work, this one is my go to and reasonably priced. I have abused, dropped and whatever you can do to a meter and this keeps doing it's job. This is not an AI review. I am responsible.... Caveat-Don't loose the little screw when you are replacing the batteries...hard to find if you are as old as me.

Good meter except for the fact that the backlight times out after about 10 seconds. I contacted customer service and they recommended a replacement meter that would not time out the backlight. DM6000AR is the model.

I already have the big brother to this meter and like it so much I tried this 4000 count one as well since the price is so low right now, I might like this smaller one a bit better than the larger one in some ways. For $17.99 and free shipping I simply have no real meaningful complaints, if any it would be the plugs would seem like they fit loose, but in all my testing and jiggling it does not seem to affect the electrical connection one bit, its just a result of matching this particular type plug in with the usual split jacks and the electrical connection itself doesnt show any effects from this it just seems to be the physical fit - ive never seen it affect the displayed number. I like this one as much or more than its big brother partly as this one has a better looking backlight. The blue backlight on the larger model has an odd washed out effect on the digits but the display is still very readable. This DT132A has a nice looking white backlight that I have no issues with other than like most it doesnt stay on long enough. As with its larger 6000 count brother theres a good deal of functionality here for the money, and ive found it very accurate in the main volt ohm cap ranges etc and it even reads temps without the thermocouple inserted if desired, and reads within 2 - 3 degrees - mine does at least. The continuity range has good volume, is reasonably fast and its even better after cleaning the tips with fine steel wool and alcohol. As with all meters in this price range theres little in the way of serious input protection, so use it accordingly its not an industrial plant meter its a home/hobby meter and given the price point and functionality im fine with that.

After an intense review of what was available in the digital multi-meter (DMM) product space, I purchased four AstroAI TRMS 4000 meters based on competitive pricing with similar products with similar specifications. These multi-meters were purchased for use by middle and high school students that are participating in the National Science Olympiad program. The features that were required were simple to use, has an easy to read display, is both precise and has acceptable uncertainty, in a physical package that could withstand the abuse/misuse of the students. Most of the digital multi-meters in this same price category, as the TRMS 4000 were NOT auto ranging or too small to have a reasonable size display. The meters with similar features by Fluke, Extech and Amprobe, to name a few, varied in price from ten to twice as expensive. Since I needed four, all of those meters were immediately ruled out. When the TRMS 4000 meter arrived, a quick physical, hands on inspection, revealed a solid design that was well labeled, with an LCD display that was about the same size as my personal hand held Fluke DMM. To test the meters, I used a variety of batteries and precision one-percent resistors to compare the performance of each meter, against my Fluke and against each other. In all cases the TRMS 4000 meters within +/- 4 least significant digits in the three and a half digit mode and +/- 2 least significant digits in the three digit mode. Without doing any real statistical analysis and without true NIST traceable standards, I feel comfortable that these meters were precise with an uncertainty that was within 1% +/- 1 digit in the tested ranges, which seems to correlate well with AstroAI’s stated specification. I should note that the results I obtained with precision resistors was well within the stated specifications. Since these we to be used for Science Olympiad competition, and the general rules prohibit using dangerous voltages, I did not test the AC or higher DC voltage ranges. However seeing the excellent results with low voltage DC and resistance, I would feel comfortable using one of these as troubleshooting tool in a professional capacity on low frequency equipment and appliances. Because TRMS 4000 has a specified input impedance of 10 Meg Ohms, I would not recommend this for use on sensitive instrumentation or high frequency circuits where test input impedances > 100 Meg are recommended and generally required. I would also recommend not using any hand-held multimeter for directly measuring currents in excess of 1 amp even though they may be equipped to do so, external shuts should be used for these types of measurements. In summary, for the price, this is an excellent choice for the serious hobbyist and student. If I had it to do over, I would still purchase these DMMs.

Indispensable tool. Great value.

Para trabajos sencillos es ideal. Es autompatico y no requiere muchos conocimiento especiales para que pueda ayudar en la identificación de voltajes y funciones especiales. Con un sencillo acercamiento al manual, se puede usar sin problemas.

I've had the AstroAI DT132A multimeter for just a few of days so far and can report some impressions. First, it is astonishing the features packed into this DMM: auto/manual ranging, min/max, relative measurement, hold function, temperature, true RMS and 4000 counts. All for $23. We owe all that to the single DreamTech DMM chip inside. The same chip is used for many brands of meters. I have not opened the case but from viewing a teardown video, the innards are sparse indeed with few other components but it does look to have some input protection components. For my use the 4000 count display is more than adequate. In many years of electronic work only a few times have I needed more than the four digits of precision that this meter provides. The single sheet manual with microscopic font size is adequate but barely. Note that the 145x70x35mm dimensions it gives for the meter are incorrect. If you're shopping for a case, the actual dimensions are: 155x75x35mm. Many, if not most, multimeters have separate banana jacks for current measurement vs. the voltage, capacitance, etc. combo input jack. This meter does have a separate input jack for the 10A current measurement but it uses the combo input jack for uA and mA current ranges. The good: convenient to not have to unplug and re-plug for a current measurement. The bad: if the probes are connected to measure a voltage, say with alligator clips, and you even momentarily switch the rotary switch to the uA or mA setting IT COULD FRY THE METER. At best it would blow the 500mA fuse, at worst it could burn the circuit board. The instruction sheet does state: THE MANUAL ROTARY SWITCH SHOULD BE PLACED IN THE CORRECT POSITION BEFORE MEASUREMENT AND SHOULD NOT BE MOVED DURING MEASUREMENT TO PREVENT DAMAGE TO THE METER. Some reviewers have complained about the beeping at every setting change. I like it because some SELECT button settings don't apply to some rotary switch positions so it will not beep for those. The beep provides some feedback that the setting will be applied. It does have the red outer moulding of soft-ish plastic, but it's only 0.1" thick so it will provide only minimal protection in a drop. The kick stand is flimsy and easily bendable. One surprise is that it came with the three AAA batteries installed--not just placed in the box. As other reviewers have stated, the backlight stays on for only 15 seconds then the button must be long-pressed to re-light. If you need to use the meter in low-light environment you'll get tired of that. If there is some cryptic button sequence that changes that timing, I'd like to hear about it. Overall, it's a remarkable feature-rich meter at a bargain price but with flimsy construction. I'll subtract one star for the thin rubber overmould and backlight timing.