Affordable UNI-T Digital Multimeter for Beginners: Best Models for Computer Component Diagnosis

I want to treat myself to an inexpensive digital multimeter. Browsing through other topics, I often came across flattering opinions about U-NIT meters.
Recommend something universal, with an indication of diagnosing computer components (e.g. measuring voltages in power supplies).

I warn you that I am a beginner amateur, a hobbyist in this field.

I limited the selection to the M890 model, which seems to be a sufficient measure for my moderate needs and modest skills.
I just don't know which one to choose, because there are several 890s, marked with the letters C, F or G, which, as I understand it, means some additional function.
Can any of you advise which one will be the best for checking computer components?

It depends what you mean by "inexpensive". If I can recommend it, it's the UT70A. Additional advantages: the ability to measure coils, capacitors, frequencies up to 20MHz, logic state indicator with a signal at LOW, holding the result, displaying the highest result. Disadvantage, quickly devours the battery on the measurement of inductors and capacitors. The price is decent for so many additional functions and the meter itself is solidly made.

I have Unita what my friend the author proposes and it works great I am very pleased and recommend it It really depends on what you need... not everyone needs frequency and capacitance measurement.

Felek Trodaj wrote:

I just don't know which one to choose, because there are several 890s, marked with the letters C, F or G, which, as I understand it, means some additional function.
Can any of you advise which one will be the best for checking computer components?

No matter which one you choose will be suitable. They differ in details that are not important from your point of view. The disadvantages they have is the lack of automatic range conversion.
Regarding UNI-T meters, I do not recommend it. It's generally crap. Poorly secured (if they have any protection at all on individual ranges). In addition, they have weak rotary switches that start to fail quite quickly.
In addition, I recommend buying, even the cheapest meter with automatic range change. It is certainly more resistant to routine and operator errors.
Of the cheaper ones, MASTECH MY-68 will meet the above conditions and can be purchased on a well-known auction site for PLN 70-90. It has everything you need and gives the impression of being very decent.

Regards

I've had the UT70A for a good few years and nothing bad has happened yet.
I bought it then for PLN 230. Now I see that it costs about PLN 150.

LuckyDj - mine is also a few nice years old, has gone through a lot and is doing great, in my life I will not believe in some faulty switches etc.

On the other hand, automatic range change - I personally do not recommend it because you have to wait until the meter goes through all ranges and finally shows the measured value. After all, we know what voltage we are measuring and we set the appropriate range - the effect: immediate result.

As for the additional functions - at first I thought that an ordinary meter would be enough for me, but over time there was a need to perform more exotic measurements, so it's worth paying extra and buying something that will last longer

manekinen wrote:

LuckyDj - mine is also a few nice years old, has been through a lot and is doing great, in my life I will not believe in some faulty switches etc.

We have a lot of them at school, unfortunately many of them are having problems with the rotary switch. On the basis of 1 piece you exploit, do not draw too far-reaching conclusions.

manekinen wrote:

LuckyDj
On the other hand, automatic range change - I personally do not recommend it because you have to wait until the meter goes through all ranges and finally shows the measured value. After all, we know what voltage we are measuring and we set the appropriate range - the effect: immediate result.

Not true, in a decent meter with an automatic machine you get the result right away. You don't have to wait for anything. Now think about what will happen to your UNI-T when you connect 230V on the 200mV range
Of course, in a meter with an automatic and well-protected device, nothing will happen.
With us, many meters failed precisely because someone accidentally set the wrong range. In addition, we do not always know what voltage we are measuring. Often it is just a suspicion and then the results are different or end up damaging the meter or its range.
Regards

Quote:

In School we have many

That clears up many things.

Quote:

In addition, we do not always know what voltage we are measuring.

And I don't understand it at all :(

It seems to me that we probably know what kind of device we are dealing with and what voltages we can expect in it, if we do not know, then we should change our profession.

In addition, we have a range of 1000V/750V at our disposal and, not being sure about the measured voltage, we start from this range.

If you expect higher voltages, then do not measure DT with this, because even cables have insulation up to 1kV.

Regards.

>> Moreover, we do not always know what voltage we are measuring.
>I don't understand it at all
> It seems to me that we probably know what kind of device we are dealing with and what > voltages we can expect in it, if we do not know, then we should change our profession.

Perhaps you do not yet have enough practical experience in this field if you think so. There are cases that you have, for example, to repair a device and you do not have a schematic or any documentation for it. The device is built into, for example, a wardrobe and you have to "disconnect" it. So you start exploring certain points. However, you don't know what tensions to expect there. Maybe mV but maybe hundreds of volts.
You have to start from the highest range and I do NOT have this problem with the machine.

>Besides, we have a range of 1000V/750V and, not being sure about the measured voltage, we start from this range.

Well, you have to spin and look for the right range, and the machine will find it in less than 1 second.
In addition, usually each machine also has a manual mode if someone insists that they need to change the ranges themselves (sometimes it is useful).

>If you expect higher voltages, then do not measure DT with this, because even cables >have insulation up to 1kV.

Believe me, sometimes you don't know what to expect. However, at home or in a workshop, you are unlikely to encounter more than 500V, unless you repair TVs.

And yours, what is the largest ACV/DCV measurement range?
Because for me, moving the switch by these two or three positions is not a special problem.
With the rest, the discussion about the superiority of an automaton over a non-automaton is at least pointless.

Quote:

On the basis of 1 piece you exploit, do not draw too far-reaching conclusions.

You draw conclusions based on one broken switch.

You wrote that you use these meters at school, so I'm 100% sure that it was damaged by someone's stupidity, not a poor quality switch.

The meter you propose to your colleague has the same ACV and DCV range as UT, so you will not measure higher voltages with it either. It also does not measure inductance, temperature and logic states. Besides, I don't think it's a good meter for PLN 70 ... but it has an automatic device :D

Unfortunately, as of today, in this and other cases, the price is an exponent of quality.

LuckyDj wrote:

And yours, what is the largest ACV/DCV measurement range?
Because for me, moving the switch by these two or three positions is not a special problem.

Depends which one, but most are 750/1000V. Switching is the problem, you say that because you've never used an automatic. Give it a try and you'll probably change your mind.

LuckyDj wrote:

You draw conclusions based on one broken switch.
You wrote that you use these meters at school, so I'm 100% sure that it was damaged by someone's stupidity, not a poor quality switch.

I draw a sentence based on many UNI-T in which the switch from constantly changing ranges is defective. Young people perform various exercises and are forced to turn the switch every now and then. This causes accelerated wear of the contact pads on the PCB (they wear out) and stop connecting. This is not related to stupidity or wrong setting of the range, but only to this defect of the meter with manual range change.

LuckyDj wrote:

The meter you propose to your colleague has the same ACV and DCV range as UT, so you will not measure higher voltages with it either.

I do not suggest measuring higher voltages to anyone and I have not written about anything like that anywhere. I only suggest that you refrain from buying UNI-T and focus on other meters, taking into account that it should have a built-in automatic device that increases the durability of the device, facilitates measurements and often protects against routine. What is the maximum AC/DC voltage is the least important.

LuckyDj wrote:

It also does not measure inductance, temperature and logic states. Besides, I don't think it's a good meter for PLN 70 ... but it has an automatic device

It's better than most UNI-T, because it's hard to find a meter worse than UNI-T.
This is my opinion based on the use of a number of pieces there.
I consider the measurement of inductance or capacitance using the time constant method to be unnecessary and practically useless as other gadgets of this type. Still measuring the temperature makes sense.

LuckyDj wrote:

Unfortunately, as of today, in this and other cases, the price is an exponent of quality.

In meters, the price is not very often an exponent of quality or functionality. I know it very well, because I use meters of various brands and types myself.

We talked about meters from the M-890, basically the lowest shelf. I found the MY-68 at this price, which, apart from the fact that it has an automatic, looks more solid than the M-890.
I prefer to buy a machine for PLN 70, since I have such an opportunity, than to kill myself with constantly switching ranges in the m-890 meter for the same money.
In addition, the MY-68 has:
-display 3 and 3/4, not 3 and 1/2 as in M-890
- memory of the last measurement,
- bargraph
-holder included
-

Hi.

Listen Tom, it's not that I want to argue, but a colleague in the subject asked about buying a UNI-T meter, so you can see he has already chosen the company. Now it's about the model, and as for the UT70A, I can confidently recommend it. Provided that no one will turn the switch left and right without sense (as it happens at school, because the teacher is not there and it clicks nicely) I do not turn unnecessarily and I have had it for several years.

Maybe you have more experience than me (after all, I'm interested in electronics for only 15 years), I don't deny it.

Thank you, gentlemen, for your suggestions, advice and explanations.

I already bought a meter. I chose the UNI-T M890C.
I believe that for my needs and a modest budget, it is a relatively good choice.

The cheapest MY-68, which was suggested by ^ToM^, is, however, more expensive than the cheapest UNI-T M890 by PLN 39 (Allegro). It decided.

I will not use the meter often, and if I do, with care, so the manual rotary switches will not be strained.

Thanks again.
For my part, I consider the matter closed.

Maybe someone will like it.

^ToM^ wrote:

Depends which one, but most are 750/1000V. Switching is the problem, you say that because you've never used an automatic. Give it a try and you'll probably change your mind.

Cheap machines suck... And the better ones (read: practical and functional) are expensive, and my friend wants a rather cheap meter.

^ToM^ wrote:

I draw a sentence based on many UNI-T in which the switch from constantly changing ranges is defective. Young people perform various exercises and are forced to turn the switch every now and then. This causes accelerated wear of the contact pads on the PCB (they wear out) and stop connecting. This is not related to stupidity or wrong setting of the range, but only to this defect of the meter with manual range change.

My friend didn't write anything that he wanted a meter for school, only for himself at home.

^ToM^ wrote:

It's better than most UNI-T, because it's hard to find a meter worse than UNI-T. This is my opinion based on the use of a number of pieces there.
I consider the measurement of inductance or capacitance using the time constant method to be unnecessary and practically useless as other gadgets of this type. Still measuring the temperature makes sense.

Estimating the value of a suspicious item is not useful? I'm kidding...

The automaton can be annoying, because when you see "230" you still have to check whether V or mV, and this is small print. Greater security is nonsense and a myth, because how does this machine work? We hold the probes in our hands, the voltage between them is 0V, the meter on the mV range and put it in the socket - bam! and nothing happens, the meter quickly changes the range to 750V and shows. And nothing will be damaged, because there is always the same 1Megaohm resistor at the input, regardless of the range, be it automatic or manual. Everything is decided by the second part of the divider and "soft".

I personally have a UT 70A meter and I am very happy with it, I have no problems with it, and it has an inductance measurement which is also useful.
^ToM^ don't be too guided by the equipment from school because I know how it is at school if you hit some ten madmen, even the best equipment will not last, such as Fluke.

At least Fluke makes multimeters that would have a slim chance of surviving in an environment as extreme as a school or university lab: http://www.eevblog.com/2010/03/07/eevblog-66-death-destruction- of-a-fluke-multimeter/ .