I see many people excited but this meter has the crappiest AC bandwidth , no bargraph , so beside beeing cheap what is the point buying it for electronics ? And I doubt any professional electrician would trust a company like this for his life ...
At this price the quality can't be good , I'm sorry but good things don't come free ... I don't want to be evil but first check if those fuses are't just chinese fakes . They know by now how much people love big fuses
To be fair, I don't trust Uni-T either, but the actual physical construction and the PCB are made to a higher standard than a lot of their previous models. I was just curious as to what the meter feels like so I bought it to check it out. If you wanna depend your life on it? That'd be crazy, and I wouldn't do that either, but for someone who's looking for a cheaper alternative with relatively good quality (compared to those absolute cheapies), it does feel a lot better in the hand, and the measurements are consistent, screen is big and fonts are bold, not to mention the great backlight feature and the beeping diode mode.
I see nothing wrong with these cheaper alternatives. They have a place in the market, and I see no prob Uni-T actually try to improve the quality of their cheapies.
EDIT:
Again, is 500Hz bandwidth too different from 800Hz? Is a crappy bargraph worth having? Name me a few meters that have decent bargraph in the $60-$70 range that has similar fit and finish and construction? The UT61E seems to be a lot better in this regard, but it was not built in the same way. Nothing is free I guess as you said.
What I'm really trying to say is, nothing is free. You get something, you lose something. I don't believe you'd be able to get a UT61E successor in this kind of build quality for a similar price. Well that hasn't happened yet, so we'll see.
It has an ETL certification, as embossed at the back of the meter and as stated in the Chinese user manual.
(Intertek's Electrical Testing Labs)
Looks like it would be around $100 USD with tax and shipping, for a 6000 count UNI-T. What's this great back light feature you keep mentioning? The fact it actually has one? Or can you leave it on forever until the battery drains?
EDIT:
Again, is 500Hz bandwidth too different from 800Hz? Is a crappy bargraph worth having? Name me a few meters that have decent bargraph in the $60-$70 range that has similar fit and finish and construction? The UT61E seems to be a lot better in this regard, but it was not built in the same way. Nothing is free I guess as you said.
What I'm really trying to say is, nothing is free. You get something, you lose something. I don't believe you'd be able to get a UT61E successor in this kind of build quality for a similar price. Well that hasn't happened yet, so we'll see.
Looks like it would be around $100 USD with tax and shipping, for a 6000 count UNI-T. What's this great back light feature you keep mentioning? The fact it actually has one? Or can you leave it on forever until the battery drains?
Well, it's only $100 AUD shipped including the Australian GST:
And this one is $94 AUD shipped including our tax:
The backlight is way more convenient to use than their other models. It's light sensing. It'll stay on forever if ambient environment is dark enough. It'll time out in maybe 20 seconds if not, then enabling it again is not as gruelling as the 139C/E models where you have to hold a button for 2 seconds. Just cover the light sensor and it'll come on. Completely disabling it is just a press of a button.
Hard to say how it would hold up. It looks like the high speed clamps are tied to the return path for the MOVs.
If this is true, it's interesting that they would talk about the 30K cycle test. We could run it to 50K full cycles and see if there is anything left.
If the whimmpy grill starter didn't damage it and it survived my smaller generator (6KVish), that would be a big improvement for UNI-T. The 138C can't come anywhere near that.
It has an ETL certification, as embossed at the back of the meter and as stated in the Chinese user manual.
(Intertek's Electrical Testing Labs)
After seeing Dave's 121GW get ETL cert and not even be able to do simple autorange, I have little confidence in their ability.
It's interesting that Fluke used to send them to several agencies, I suspect partly to avoid having a test house that replaced their senior staff with fresh outs who have no idea what a DMM is, just to make more profit. Surely this couldn't happen.
With Dave's new meter having a UL cert, it will be interesting to see if it follows a similar path. So far, that lack of transparency and leaking a little bit here and there, it sure seems like this it the path it is heading down.
If this is true, it's interesting that they would talk about the 30K cycle test. We could run it to 50K full cycles and see if there is anything left.Well, truth be told, either 30k or 50k is a very respectable lifetime for the switch. The issue is believing if they are a design feature or instead simply a "prepared" unit.
If the whimmpy grill starter didn't damage it and it survived my smaller generator (6KVish), that would be a big improvement for UNI-T. The 138C can't come anywhere near that.Are you referring to the UT139C? If so, in your tests it went up to 5kV. I wouldn't necessarily classify it as "can't come anywhere near that".
It has an ETL certification, as embossed at the back of the meter and as stated in the Chinese user manual.
(Intertek's Electrical Testing Labs)
After seeing Dave's 121GW get ETL cert and not even be able to do simple autorange, I have little confidence in their ability.We mentioned this somewhere else; there is a possibility the test procedure does not exercise or cover this scenario. It is a somewhat CYA operation.
It's interesting that Fluke used to send them to several agencies, I suspect partly to avoid having a test house that replaced their senior staff with fresh outs who have no idea what a DMM is, just to make more profit. Surely this couldn't happen.I wouldn't be surprised that Fluke, having created or shared a great deal of the practices and design rules that inspired the standards, would get these certifications done for pennies on the dollar.With Dave's new meter having a UL cert, it will be interesting to see if it follows a similar path. So far, that lack of transparency and leaking a little bit here and there, it sure seems like this it the path it is heading down.Just like you, I think that a decent equipment is mostly tied to the OEM than to the standard itself.
If this is true, it's interesting that they would talk about the 30K cycle test. We could run it to 50K full cycles and see if there is anything left.Well, truth be told, either 30k or 50k is a very respectable lifetime for the switch. The issue is believing if they are a design feature or instead simply a "prepared" unit.
They may spit shine them every 5,000 cycles like Dave demonstrated.
The Fluke 101 surpassed it by a very large margin. Still to this day, I am not sure by how much as the 101 has yet to be damaged.
I consider anything that can't compete with the AMPROBE AM510 not to be robust.
(...)
I know many people whined about how the 139C performed.
(...)
You may see these numbers as being too harsh.
Yeah when that person had brought up HIOKI being self certified, it's a good case and point.
***
Was going to mention that I believe the AMPROBE AM-510 was certified by Intertek and made by UNI-T (see attached). Of course, the same companies produced and certified the AM-530. The 510 far surpassed the 530 in my testing. Just shows that if you make enough products, eventually you may stumble on a combination that is better than others. Design by random chance.
If this is true, it's interesting that they would talk about the 30K cycle test. We could run it to 50K full cycles and see if there is anything left.Well, truth be told, either 30k or 50k is a very respectable lifetime for the switch. The issue is believing if they are a design feature or instead simply a "prepared" unit.
They may spit shine them every 5,000 cycles like Dave demonstrated.I didn't remember this. If they did so, then it would not be very realistic.
The Fluke 101 surpassed it by a very large margin. Still to this day, I am not sure by how much as the 101 has yet to be damaged.Yes, the little Fluke is still the one to beat. However, I had a few quality problems with two very different units built with two different date codes that it reduced my trust significantly on them.I consider anything that can't compete with the AMPROBE AM510 not to be robust.
(...)
I know many people whined about how the 139C performed.
(...)
You may see these numbers as being too harsh.I have zero skin in the game. I don't care one way or another either, but my comment is about words, not numbers. Thanks for providing the parameter of "joeq's standard of robustness" (TM)
Yeah when that person had brought up HIOKI being self certified, it's a good case and point.
***
Was going to mention that I believe the AMPROBE AM-510 was certified by Intertek and made by UNI-T (see attached). Of course, the same companies produced and certified the AM-530. The 510 far surpassed the 530 in my testing. Just shows that if you make enough products, eventually you may stumble on a combination that is better than others. Design by random chance.I was going to comment that as well. The AM530 seems quite alright w.r.t. input protection but it may simply be a weakness brought by the added features.
I've seen similar comments about the added features being to cause of the weakness. I never understood that. If UNI-T wants to design products that survive, then they just need to put the effort in. I've looked at a lot of meters with far more features than the 139C that could easily survive that 6KV transient and weak grill starter. Pretty much every Brymen and Fluke I have looked at had no problems. Even that Gossen Ultra with it's lack of shields survived everything I put it through. I would imagine the difference is the skill set of their designers compared with UNI-T is all. That or the designers are not asked to come up with robust designs. That's certainly possible.
I've seen similar comments about the added features being to cause of the weakness. I never understood that. If UNI-T wants to design products that survive, then they just need to put the effort in. I've looked at a lot of meters with far more features than the 139C that could easily survive that 6KV transient and weak grill starter. Pretty much every Brymen and Fluke I have looked at had no problems. Even that Gossen Ultra with it's lack of shields survived everything I put it through. I would imagine the difference is the skill set of their designers compared with UNI-T is all. That or the designers are not asked to come up with robust designs. That's certainly possible.We talked about this somewhere else as well: the standard seems to not give a damn for the survivability of the circuit itself, as long as the damage does not cause harm to the operator. Sure, the more intact the meter is after an event, the better, but it is impossible to have a 1:1 correlation between your tests and whatever the cert agencies put out.
(Special case for the Gossen, which actually changes its status due to magnetic forces, showing an incredible gap in testing).
However, my comment is that the survival chances of a circuit can be due to many factors, ranging from improper input protection to changes on the IC design. The IC used on the AM510 could be borderline above the input transient, while the AM530 could be internally weakened by an internal switch, mux or even a floating GPIO or anything else, really. That could be evidenced by your tests if a simple Ctrl-C+Ctrl-V of the input protection circuitry was done across these two models. Given the amount of damage between the two could simply be a small "poof" on the main IC and the physical integrity is intact, that becomes a non-issue for the manufacturer.
I always recall an ancient video of Dave and Doug blowing up meters with a 40J pulse, where the most potentially dangerous was indeed a Fluke 7x series (it was a 75 IIRC), where the rotary dial flew off at a high speed.
Still to this date, I couldn't tell you if the spirit of the standards is that the meters must survive or not. I have presented sections from the standards that I would tend to interpret that the must survive. Obviously a lot of meters would not, at least the way I test them. Some have UL approval. So yeah, hard to say. Again talking directly with Fluke, I was told they design them to survive these test. I spoke with another large company who were on the opposite end of the spectrum.
Still to this date, I couldn't tell you if the spirit of the standards is that the meters must survive or not. I have presented sections from the standards that I would tend to interpret that the must survive. Obviously a lot of meters would not, at least the way I test them. Some have UL approval. So yeah, hard to say. Again talking directly with Fluke, I was told they design them to survive these test. I spoke with another large company who were on the opposite end of the spectrum.
Joe,
I don't have the expertise that you do, on this subject, as a matter of fact, I am way out of my league. I do not disagree that manufacturers cannot design and build resilient meters capable to surviving the conditions of the safety standards and keep on being used. However, one thought that I have that manufacturers have a legitimate reason for having their meters NOT survive the conditions of the standard, but provide protection to the user. That reason is that they likely cannot guarantee that the meter will survive multiple exposures to the standard. To have a meter survive and remain in service (let's face it, an electrician is NOT going to replace a meter if it's not broken) after being exposed to the highest level of exposure of the standard is asking for a lawsuit should the meter not survive a subsequent exposure. To give an analogous example, when I was involved in a car accident on my way home from work, I had a child seat in the back seat, but my child was not with me. (Edit to add: All the damage was to the front end, no damage to the back passenger area and there was nothing in the child safety seat. End Edit) Despite that, and because of the severity of the accident (the car was totaled) my insurance company said that I had to replace the car seat because they would not pay for medical costs to my child should I decide to re-use the car seat in my next car and if that car was involved in an accident while my child was in the child seat. True story. We did not hesitate to replace the car seat. I can see meter manufacturers doing a similar calculation as my insurance company and deciding to make a meter that will protect the user for a one-time exposure, but after that exposure, the meter will not be usable.
Of course this does not absolve the manufacturers of meters who can't make a meter that at least protects the user from conditions in the standard or that lie about being tested to the standard.
This is just another POV. I'm not saying I'm right, just saying that there is likely more to the calculation than I have seen put forward until now.
Q) These test are irrelevant over what is rated, is like you smash a car at 2 mach and say "ehh car not good, unsafe, bla bla" whats the point of using a meter over the rated point???
A) Cars are subjected to some pretty harsh testing as well to insure the safety of the passengers. Most of us don't drive our cars head on into concrete like the test dummies. Maybe read the IEC standards or just do some simple Google searches on surge testing and what you are going to find out is the tests I show are a joke. Not that they are as harsh as you make them out to be, but rather that they no where near as harsh as the real tests are. And again, if I were interested in considering how safe a meter was, I would be testing differently but I'm only concerned with the robustness of the meter's front end.
Still to this date, I couldn't tell you if the spirit of the standards is that the meters must survive or not. I have presented sections from the standards that I would tend to interpret that the must survive. Obviously a lot of meters would not, at least the way I test them. Some have UL approval. So yeah, hard to say. Again talking directly with Fluke, I was told they design them to survive these test. I spoke with another large company who were on the opposite end of the spectrum.
"...but it is impossible to have a 1:1 correlation between your tests and whatever the cert agencies put out."
It's good to finally see comments like this echoed.
No doubt there can be many causes for damage. Countless. If the design goals are clear, I have no doubt that a team of competent designers could achieve it assuming there is some give and take in cost and such.
The 121GW is also odd as in that case is we have Dave, the expert in DMMs and super critical of all poorly designed products approving it. By approving, I mean allowing them use of his brand and also directly selling the product. I wouldn't necessary have thought the meter would be robust but I would have expected it to be fairly solid from all other aspects.
If we deviate to David's meter , let's admit that he did't had time himself , then he should have done initial beta testing , simply borrowing some meters to serious hobbyists ( not fanboys to tell how good it is ) ... then all the issues should have been discovered and corrected before releasing .
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Also, by sending one of the prototypes to Joe, it seems he was looking past the "yes men" you aluded - the meter failed miserably in several fronts.
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Also, by sending one of the prototypes to Joe, it seems he was looking past the "yes men" you aluded - the meter failed miserably in several fronts.
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I honestly don't think he knew or understood that I was benchmarking them while also dissecting them under the microscope. Maybe people were filling his head with stories of meter exploding drama. I know he was really just looking for me to blow the thing up and I was looking to what we could learn from it. In the end, I think he felt it was a mistake and I can't say I disagree.