Personally, when I think bench meter, I am thinking low end is my 34401A. Great meter. Really like it. Replacing that with a handheld is more what I am after in a portable bench meter. But my hobbies are going to be different than others. If you don't need anything more than the KT6000 and it's few shortcomings, good deal. Same for the free HF meter.
Even used on eBay, 34401A is 18x the cost of the AN860B. The Aneng topic was aimed strictly at 'no budget' entry level meters. We could expand the discussion to include my Fluke 189 as a handheld meter but not a lot of newcomers want to put out that much money for their first multimeter (that, and it's out of production).
The EEVblog meter seems to have some quirks when measuring frequency as well. First of all, the ACV reading has to be correctly scaled and then, maybe, it will read frequency if it isn't too fast. But you're right, the AN860B doesn't do frequency counting without a zero crossing.
I get a lot of questions that basically go something like, I bought this meter, can you show me how to improve it. Sadly people often must feel cost is everything. I bought the 34401A new when it first came out. Cost of ownership has been next to nothing. And again, not suggesting that people run out and buy one only that this is what I consider a basic bench meter and it has served me very well over the years. I bring up the HF free meters because in some cases, they may be good enough. They are better than what I started out with.
I saw that same problem with the KT6000. Good luck getting even a MHz out of the counter in volts mode. Best to stick with the mV setting. Then again the HF meter can't measure frequency. For the $20 to $50 cost of the KT6000, hands down I would take the 61E. And I am no fan boy when it comes to UNI-T!
Yea, I'm sure I would damage it sooner or later but it's more in line with what I want on the bench. In the garage or light electrical, I still like the 101 and that UT210E.
Had I ran the meter at 8KV or 15KV, it would be rare any testing I show would result in a meter failing to the level where it would cause an operator injury. Of course, I've posted that what 50 times now.
Maybe I could make a suggestion, in your videos, in the description, put a link to where you describe your general torture tests and how that relates to CAT, or real world, why you chose those test conditions.
There is a FAQ linked right off the main page in both the about and discussions area but I doubt people read it. There is also the large thread that details much of it, but again I doubt many people read it. I have made specific videos about the tests as well but the hits are low. People just like thinking it has something to do with safety.
These Q/As are from the FAQ(questions supplied by viewers):
Q) Are the meters that fail your tests unsafe? They all fail in a safe manner and although non-functional it presented no safety risk in that failed condition.
A) I have no idea if any of the meters I have looked at would fail in a safe manner or not if tested to the IEC standards. If you want to know if a meter is safe or not, have it tested by an accredited lab or buy one that has been certified by a third party.
I loosely based my testing on the IEC standards. The tests I perform are at much lower energy levels than the meters what these standards call out. This is why we never see the explosions like you would when watching some of Fluke's internal testing. I don't expect the general hobbyist is going to know about CAT ratings or the IEC standards.
Q) How extreme are the tests you perform?
A) Compared with the IEC standards they would normally be tested against to be certified not very. The energy levels I use are much less than what is called out.
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.
Q) I don't understand the point of testing these meters beyond their specifications. It says right on the front of the Brymen: "1000v" with CAT IV; why go beyond this?
You NEED that high voltage probe you showed in another video if you even suspect transients are above spec limits -- unless you are as brief as, say, an ESD pulse.
A) The ESD pulse is going to be measured in ns. I do run a sort of ESD test on these meters using a Piezo gas grill starter. While the IEC standards call for a 50us FWHH, I have been running all of the low voltage (< 6KV) with a 100us FWHH. The higher transients are now running with a 50us FWHH. This would allow someone to repeat these tests. Keep in mind that combo generator's designed for the IEC standards will have a different current waveform. The generator I built is limited to around 20 joules. The majority of the testing is below 10 joules! Now where near the real IEC. If you want to see some real damage, watch some of Fluke’s surge test videos. While the meter is marked CAT IV 1000 this calls for a 12KV, 1.2/50 us surge with a 2 ohm source. Granted, Brymen told me they expected the meter would be damaged when I ran the 6KV transient. I was impressed when it survived. Using the high voltage probe does not make a lot of sense. None of the ones I show, including my home made ones are rated for high energy applications.
Q) What is the point of applying 5kV to a meter which is rated for 600V
A) You are correct that the manual for the UT139C states the "Maximum input voltage: 600 Vrms". To be clear, Vrms would be the same for both AC and DC but not at all for the waveforms I apply during these tests. The part you appear to not understand is that many of these meters are specified to meet a certain IEC standard. In the case of the UT139C, the manual states "Safety Standard" IEC/EN 61010-1: CATIII600V" This is the first version of the standard and has a maximum of 6000 Volts using a 2 ohm source impedance. The waveshapes (open/shorted) are called out in the standard along with the five +/- transients. Now all that said, I am not testing to this standard. The width of the pulse being applied is double for the 6KV and less tests. The other major difference is I limit the energy available to the meter for safety reasons. Typically this has been less than 10 Joules but I have ran some near 20 Joules. The reason for the tests is simple, to find which meters are more robust electrically than others. This is why they are all tested to failure (for the most part).
Q) Well, did you ever tried to develop something and pass EMC tests?
I guess no. Do you know how surge protection components work? I guess you have no idea. The energy of surge pulse is enormous. The way you are testing is nonsense. The standard is defining sequence of pulses to simulate possible real situation. It means that after each applying of this pulse sequence is required to let device protection circuits cool down (if standard does not say to repeat twice etc.). Otherwise you will face situation, that circuits must be 10-20 times stronger than necessary. You are simply destroying them by heat accumulated by quick repetition of test sequences. There is no time to even transfer accumulated energy from chip to package. And this is exactly what you are doing. So remove all multimeters from trash and start again please. I do not say that multimeter which survived your handling is bad. But it does not mean that others are not fulfilling standards. They are just not so "idiot resistant".
A) It seems you do not comprehend what is going on so once again, let me attempt to explain. Let's start with some basics. The EMC standard is different from the safety standard. The EMC standard is 61326. The safety standard is 61010. Your comments are about surge, so I'll assume this is just a mistake on your part. You are correct, the energy in a combo generator that would normally be used for the 61010 is pretty high. Consider that this is just the energy available. It's not the energy that will normally be dissipated by the device being tested. Next consider that my generator is not a combo. I have made this clear from day one. It has NEVER been my goal to look at the meters from a safety standpoint. So while my generators may closely replicate the open circuit waveforms from 61010, they are no where near what the short circuit case calls for. Again, I've explained the reasons for this several times and it should not need repeating. Consider that most meters have failed with much less than 10J applied! While testing the first batch of meters, I did not have 10J available until the finals where the Fluke 101 finally came out on top. Many of the meters are damaged before I get to the surge test. They are just that bad. In the case of the 87V, I agree that I would have never expected it to fail at such low levels. By far it was the worst of the Flukes I have looked at.?
Home
Help
Search
Login
Register
