EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: technix on May 19, 2017, 08:48:04 am
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This is about the Uni-T UT61D/E multimeter. How do you think of them?
I have a UT61D (bought to replace my dying DT890) and then I bought a UT61E as an upgrade and pushed the '61D to the background. How good are they? I also bought the USB linking cable ($3 a pop anyway, and irrelevant to the meter's accuracy.) How do you think of that accessory?
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A multi meter is nothing more than a tool to get the job done, are you hindered by these tools in getting the job done?
If not than these tools are just fine! :-+
3 dollars for a usb interface cable is just dirt cheap, but 3 dollars wasted if they're no use to you at all.
Expensive equipment doesn't make anybody a better engineer or repairman.
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A multi meter is nothing more than a tool to get the job done, are you hindered by these tools in getting the job done?
If not than these tools are just fine! :-+
There's limits to this philosophy.
eg. If I was an electrician working with mains electricity every day then I wouldn't use either of those, for safety reasons.
As far as "accuracy" goes, one of the best ways to be confident about accuracy is to own two or more meters and regularly switch between them. If you do this you'll soon see if a meter is misbehaving or not.
Also, if a reading is important you can measure it with more than one meter simultaneously. If the readings agree then it's probably correct. This last trick applies to $400 Flukes as well as cheapo meters.
(in fact two cheap meters is in many ways preferable to one expensive one)
Bottom line: If you own both a UT61D and a UT61E and you're not an electrician then you're good. :popcorn:
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eg. If I was an electrician working with mains electricity every day then I wouldn't use either of those, for safety reasons.
I have to ask why? As long as they actually comply with the relevant standard, and not fudging their testing, the UT61D is CAT. III 1000V, CAT.IV 600V. So comparable with Fluke, Keysight et al.
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eg. If I was an electrician working with mains electricity every day then I wouldn't use either of those, for safety reasons.
I have to ask why? As long as they actually comply with the relevant standard, and not fudging their testing, the UT61D is CAT. III 1000V, CAT.IV 600V. So comparable with Fluke, Keysight et al.
Uni-T is famous for not complying with the CAT ratings printed on the front.
Many of their meters also come in different internal variations. Same model number, identical on the outside but some have glass fuses instead of ceramics, some are missing PTCs and MOVs, etc, etc. You never know what you're getting.
There's many many examples of these problems on EEVBLOG, two minutes with google will convince you. Dave even did a video after he bought one for hs own personal use then was horrified after he opened it:
https://www.youtube.com/watch?v=i2Tkm21dI1g (https://www.youtube.com/watch?v=i2Tkm21dI1g)
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The UT61D and the UT61E both died on the very first test in the electrical robustness testing thread. This is something that only one other meter has managed so far.
https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/ (https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/)
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It's a shame really. Uni-T UT61/E has a really nice form factor and the screen on it is top notch, very easy to see and read.
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It's a shame really. Uni-T UT61/E has a really nice form factor and the screen on it is top notch, very easy to see and read.
It measures a lot of different things, too, and is quite accurate.
I'm not saying don't get one, just be aware.
I'd get a Fluke 101 if I regularly worked with mains electricity. Only $42 delivered and one of the safest meters available at any price.
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As far as "accuracy" goes, one of the best ways to be confident about accuracy is to own two or more meters and regularly switch between them. If you do this you'll soon see if a meter is misbehaving or not.
There's an old saying when going to sea, bring 1 compass or 3, never 2!
For circuit testing at mains voltage levels, just to prove I have something there, I prefer the solenoid style tester. I do note that Fluke would rather I use an electronic tester but the reason I like it is that I don't have to look at it. It buzzes in my hand. The harder it buzzes, the higher the voltage. It is pretty easy to differentiate between 120,208,277 and 480VAC. If I'm up in a dark space, I can even see the arc when I connect the probes. The device really jumps at 480V!
http://www.fluke.com/fluke/uses/comunidad/fluke-news-plus/articlecategories/rd/solenoid%20vs%20select%20volt%20test (http://www.fluke.com/fluke/uses/comunidad/fluke-news-plus/articlecategories/rd/solenoid%20vs%20select%20volt%20test)
I like:
https://www.amazon.com/Ideal-61-065-Vol-Test-Voltage-Tester/dp/B000BVNSLG (https://www.amazon.com/Ideal-61-065-Vol-Test-Voltage-Tester/dp/B000BVNSLG)
But I prefer the old school Knopp tester:
http://www.knoppinc.com/tools.htm#K-60 (http://www.knoppinc.com/tools.htm#K-60)
Note that the Knopp is very low impedance. This may have implications when testing relay circuits in that it is entirely possible to energize a relay through the meter. If the machine starts, really bad things could happen!
When testing for the presence of voltage (safety), I don't prefer an electronic gadget with an off-on or high-off-low switch. I have been using, but not sure I like, the Fluke tester:
http://en-us.fluke.com/products/electrical-testers/fluke-1ac-ii-a1-electrical-tester.html (http://en-us.fluke.com/products/electrical-testers/fluke-1ac-ii-a1-electrical-tester.html)
Our procedure required 3 steps: Verify the tester on a known energized circuit (preferably the one we're working on), de-energize/lock/tag and test the circuit under work and, finally, retest the tester on a known energized circuit. Even then... I still like to check with a solenoid style tester. I just don't trust those silicon diodes!
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I'd get a Fluke 101 if I regularly worked with mains electricity. Only $42 delivered and one of the safest meters available at any price.
No you wouldn't. You would use a Fluke 87, just like the rest of your co-workers, unless you wanted to be the butt of their jokes.
Don't confuse safety with Joe's 'ruggedness'. The 101 is only rated 600V CAT III.
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I'd get a Fluke 101 if I regularly worked with mains electricity. Only $42 delivered and one of the safest meters available at any price.
No you wouldn't. You would use a Fluke 87, just like the rest of your co-workers, unless you wanted to be the butt of their jokes.
Don't confuse safety with Joe's 'ruggedness'. The 101 is only rated 600V CAT III.
Addendum: "If I was on a budget" :popcorn:
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Well if you re measuring mains on sockets Cat III 600 V is good enough . But on the feeding box of a house and all cables from the outside you need Cat IV measurement equipment .
The Uni-T 61 looks fine from the outside . The display and the range switch are really fine . But just said here hundreds of times here in the forum , the different versions you get on the market make buying this multimeter to a lottery . You can get one with lacking overvoltage protection and shitty input jacks or good ones with overvoltage protection and proper fixed input jacks . The funny thing is that the good one has a lower Cat rating than the bad one , so the Cat rating of the bad one is just a fairy tale
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It's a shame really. Uni-T UT61/E has a really nice form factor and the screen on it is top notch, very easy to see and read.
It measures a lot of different things, too, and is quite accurate.
I agree that the UT61E form factor and functionalities are good.
But for the accuracy, I am not convinced. My UT61E measures 10.000 V from a breadboarded REF102 :-+. But my three 0.005% resistors are off. The readings are within the UT61E spec (0.5% +10 counts), but the readings are far from being close to spot on (up to 16 counts off when measuring a 1 K 0.005% resistor).
Do not get me wrong, it is a nice DMM (except for the shortcoming highlighted by Joe Smith's tests), but the accuracy on the resistance mode, on my unit, is not impressive.
:)
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But for the accuracy, I am not convinced. My UT61E measures 10.000 V from a breadboarded REF102 :-+. But my three 0.005% resistors are off. The readings are within the UT61E spec (0.5% +10 counts), but the readings are far from being close to spot on (up to 16 counts off when measuring a 1 K 0.005% resistor).
Use better multimeter probes or clean the probe tips with some isopropyl alcohol and some abrasive material and use the REL button.
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Uni-T is famous for not complying with the CAT ratings printed on the front.
Many of their meters also come in different internal variations. Same model number, identical on the outside but some have glass fuses instead of ceramics, some are missing PTCs and MOVs, etc, etc. You never know what you're getting.
There's many many examples of these problems on EEVBLOG, two minutes with google will convince you. Dave even did a video after he bought one for hs own personal use then was horrified after he opened it:
OK, I watched the video. I hadn't seen it before.
If I was an electrician working with mains electricity every day then I wouldn't use one of those, for safety reasons. :)
Mea culpa, Fungus, I wasn't aware of the Uni-T crappy build. Amazing how they then get to put a compliance rating onto the front of their meter without getting called out by someone within the IEC or IEEE.
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But for the accuracy, I am not convinced. My UT61E measures 10.000 V from a breadboarded REF102 :-+. But my three 0.005% resistors are off. The readings are within the UT61E spec (0.5% +10 counts), but the readings are far from being close to spot on (up to 16 counts off when measuring a 1 K 0.005% resistor).
Use better multimeter probes or clean the probe tips with some isopropyl alcohol and some abrasive material and use the REL button.
Thank you for the suggestions, but all measurements were done with with banana-to-banana test leads that are showing 0.00 to 0.01 ohm on the UT61E ;)
The factory probes were not used, but I polished the tips with Autosol metal polish.
:)
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I am not a fan of UNI-T as it just seems like they don't address basic concerns like ESD with their designs. Even bad designers can get lucky now and then and I am not suggesting that all of their products are sensitive to ESD. Just a high percentage of the ones I looked at.
Besides the sensitivity to ESD, the 61E had the second highest temperature drift of the meters I have purchased. For me, the lack of a backlight and no temperature measurement is a let down. But you do get data logging and it is a higher res meter if that is what you are after. Really, beyond those to things and that they give these things away, I don't see the interest in them.
That said, so far my badly (total understatement) chopped up UT61E performs well. It has provided me with several hours of entertainment value and I suspect will continue to do so if I think of something else to do with it.
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If I was an electrician working with mains electricity every day then I wouldn't use one of those, for safety reasons. :)
i would.
lets just put the fluke / brymen sales team to one side for a moment.
an electrician will never read current with a shunt - it's dangerous - they would use an induction coil or clamp meter.
so the fuses are irrelevent.
and mains is going to be 110 - 240v or worst case 440v.
so no amount of mov's is going to make any difference because they are rated at over 200% of your maximum working voltage.
it's people messing with stuff in labs & workshops that need the protections - an electrician is working with a known voltage range in a limited way.
of course electricians wont need 99% of that meters features though.
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If I was an electrician working with mains electricity every day then I wouldn't use one of those, for safety reasons. :)
i would.
lets just put the fluke / brymen sales team to one side for a moment.
an electrician will never read current with a shunt - it's dangerous - they would use an induction coil or clamp meter.
so the fuses are irrelevent.
and mains is going to be 110 - 240v or worst case 440v.
so no amount of mov's is going to make any difference because they are rated at over 200% of your maximum working voltage.
Sure... so long as you only ever operate it perfectly, never tired or in a hurry, you always remember to swap the lead back after measuring current, no dirt ever gets in the range selector, you never lend it to anybody, etc., etc.
Like airbags in cars, the protection is there for when things go wrong, not for when you're driving perfectly on a sunny day with nobody else around.
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I had one bought at a sale, its crap. Open it u and you`d see. The one I had stopped working after about 2 years just sitting in storage, in room (so no dust or water). Input protection on these is hillarious, if a fuse blows they appear to have zero capability to protect you (look at the case), input jacks are...well.
If I was after a very cheap meter, I`d go for Mastech, not popular but better laid out and far more robust. Otherwise you have Brymen, used Flukes (total tanks) and etc. I`ve also had devices under various brands made by Lutron, one of the biggest OEMs in Taiwan, they are total crap. My LCR meter I repaired twice in 4 years, simple cheap layout which today cannot measure inductance, by some reason, after staying unused for about 10 months...
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I agree that the UT61E form factor and functionalities are good.
But for the accuracy, I am not convinced.
If you've got all those reference values then open it up and fiddle with the calibration pots. :popcorn:
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I had one bought at a sale, its crap. Open it u and you`d see. The one I had stopped working after about 2 years just sitting in storage, in room (so no dust or water). Input protection on these is hillarious, if a fuse blows they appear to have zero capability to protect you (look at the case), input jacks are...well.
That's interesting that it stopped working just sitting in storage. Do you live where salt and humidity is a problem? Did you save the meter? If so, pull that thing apart and lets see some pictures of the insides. Curious what revision it was.
The last one I bought is not a year old yet but it's been through more than most meters would in a 30 year life span. :-DD
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That said, so far my badly (total understatement) chopped up UT61E performs well. It has provided me with several hours of entertainment value and I suspect will continue to do so if I think of something else to do with it.
Normally I'd call that cheap entertainment ($60 for several hours isn't bad at all), but after adding in $50 million of engineering time into it, I can't really call it "cheap" anymore. :-DD
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That was a conservative estimate!
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That was a conservative estimate!
:-DD
I can just see the advertisements. "The UT-61E. Now with more engineering investment than any other handheld meter (and maybe any other meter, period!) on the planet. Get yours today!"
:-DD
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I'd get a Fluke 101 if I regularly worked with mains electricity. Only $42 delivered and one of the safest meters available at any price.
No you wouldn't. You would use a Fluke 87, just like the rest of your co-workers, unless you wanted to be the butt of their jokes.
Don't confuse safety with Joe's 'ruggedness'. The 101 is only rated 600V CAT III.
I'm yet to see Fluke 87 in household electrician bag. Only name-branded meters used outside of industrial environment are ones that you need for making measurements that require calibration, certified meter and your sign on piece of paper - ie earth fault loop impedance, insulation resistance and so on.
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I'm not familiar with Poland's general attitude towards safety, but the meter should at least be rated CAT IV, with a recognized safety agency listing.
In an industrial environment, meters are provided by the company and are usually of high quality, mostly for their reliability, ruggedness and reputation in case of accident litigation.
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If you're not playing with electricity or high current, a cheap UT61 may be ok
If you might one day play with electricity or high current, get a cheap Fluke too,
a reputable company with lots of cash to sue, if the meter design was at fault, and not the operator
Try and catch up with Uni-T if one of their UTxxxA, B, C, D, E, F... monthly new models decides to go BANG! due to rushed design, visual eye candy addons or operator OOPS!
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I'm not familiar with Poland's general attitude towards safety, but the meter should at least be rated CAT IV, with a recognized safety agency listing.
In an industrial environment, meters are provided by the company and are usually of high quality, mostly for their reliability, ruggedness and reputation in case of accident litigation.
That's why I talked about non-industrial specifically. For industrial, of course, something like Fluke 87 is preferable (not that it's ideal, if we're talking about ultra-scary busbars everywhere I'd prefer something that doesn't have current via shunt measurement anyways), but for household anything more than a glorified lightbulb (one of Fluke voltsticks or an equivalent, actually Uni-T ones are ok, and even random brands - it's really hard to construct a device consisting of plastic case, thermistor, LED and a cable that won't be CAT III unless you really try) and random clamp-meter is kind of overkill.
By the way, everything a typical household electrician does is CAT III.
Blueskull, thank you:) I have no idea where this surprisingly popular idea that anything that comes close to a mains socket should be CAT IV comes from.
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In a Cat 111 scenario a Cat 4 meter (non-BS Cat 4 meter) may tolerate an 'unknown' source of surprise BANG! :o better than a Cat 3 meter,
assuming the leads are the real deal too
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Indoors only: CAT III is sufficient.
Where I live, a lot of electrical cabling is on the outside of the house: Garden lights, water pumps, pool pumps, air conditioning units. Often, 'house' electricians have to deal with those too.
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That's ambiguous. Most expanded CAT IV explanation I have read, talk about any outside wiring, due to potential lightning strike.
Here is Metrel's:
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&ved=0ahUKEwjX2OPJu4DUAhVISRoKHS1cA90QFghAMAQ&url=http%3A%2F%2Fwww.metrel.si%2Fdl%3Fd%3DPDF_dokumentacija%2FWhite_papers%2FAng%2FWhite_paper_Overvoltages_and_high_current_breakdowns.pdf&usg=AFQjCNFBhMl5Vs87dEDjna1CoMw5j6eWmA&sig2=yhVfF276xa9HxSX6ol6CXQ&cad=rjt (https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&ved=0ahUKEwjX2OPJu4DUAhVISRoKHS1cA90QFghAMAQ&url=http%3A%2F%2Fwww.metrel.si%2Fdl%3Fd%3DPDF_dokumentacija%2FWhite_papers%2FAng%2FWhite_paper_Overvoltages_and_high_current_breakdowns.pdf&usg=AFQjCNFBhMl5Vs87dEDjna1CoMw5j6eWmA&sig2=yhVfF276xa9HxSX6ol6CXQ&cad=rjt)
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Indoors only: CAT III is sufficient.
Where I live, a lot of electrical cabling is on the outside of the house: Garden lights, water pumps, pool pumps, air conditioning units. Often, 'house' electricians have to deal with those too.
I believe "outdoor" on that fluke label refers to anything before your panel, i.e. power pole, transformer. etc. and not that GFCI outlet on the side of your garage, or that fountain pump...
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If the pool pump is inside the house it s CAT III , if it is feeded outside by a socket or the connection box of the pump it is CAT IV so the safety regulation here in Germany by the employers mutual insurance association . All installations outside the house are CAT IV rated , even they are feeded from distribution boxes which are CAT III rated . The reason for this is magnetic induction caused by thunderstorms i.e.
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I'm not familiar with Poland's general attitude towards safety, but the meter should at least be rated CAT IV, with a recognized safety agency listing.
In an industrial environment, meters are provided by the company and are usually of high quality, mostly for their reliability, ruggedness and reputation in case of accident litigation.
Right , specially the company is ISO9001 certified they were forced to use quality measurement equipment to keep the quality standard of their measurements .
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Cat 4 volt sticks, gloves, glasses and rubber boots anyone ? >:D
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Cat 4 volt sticks, gloves, glasses and rubber boots anyone ? >:D
I'm not sure what your rubber boots measure if they're considered viable for CAT IV;)
By the way, the whole conundrum about CAT IV outdoor conductors is trying to codify people not sticking probes with conductor inside connected to their small plastic black box to thingies directly connected to outdoor circuits when they hear strange sounds usually associated with lightning strikes in vicinity of few kilometers.
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I'm not sure what your rubber boots measure if they're considered viable for CAT IV;)
High rubber heels? ^-^
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I'm not sure what your rubber boots measure if they're considered viable for CAT IV;)
High rubber heels? ^-^
They're okay (meaning you'll remember not to do this again, but you won't die) in case of 230V RMS. Not sure about these lightning transients. I don't advocate grabbing mains conductor whilst in rubber heels and waiting till lightning strike.
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I'm not sure what your rubber boots measure if they're considered viable for CAT IV;)
High rubber heels? ^-^
with ceramic insulator heals... lol
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I just imagine myself an electrician with a sadomaso rubber suit in a technical room >:D :-DD :palm:
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Cat 4 volt sticks, gloves, glasses and rubber boots anyone ? >:D
I'm not sure what your rubber boots measure if they're considered viable for CAT IV;)
With warm socks (and heavy duty odour eaters) they are a better bet to survive confirming voltage present outdoors,
than just bare feet or sandles standing on wet concrete, wielding a supposedly 'safer' Fluke meter ...or Uni-T 'cross your fingers' meter ;D
which I don't do anyway, if I observe dark clouds at a distance (lazy lightning can find another short path to earth, I don't need any more HV tingles)
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Cat 4 volt sticks, gloves, glasses and rubber boots anyone ? >:D
I'm not sure what your rubber boots measure if they're considered viable for CAT IV;)
With warm socks (and heavy duty odour eaters) they are a better bet to survive confirming voltage present outdoors,
than just bare feet or sandles standing on wet concrete, wielding a supposedly 'safer' Fluke meter ...or Uni-T 'cross your fingers' meter ;D
which I don't do anyway, if I observe dark clouds at a distance (lazy lightning can find another short path to earth, I don't need any more HV tingles)
Don't forget your aluminium foil hat...
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Good point, I better leave the 87V in the van too ;D
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They pose CAT4 hazard, because person using a meter isn't qualified to discriminate between "lightning more than few kilometers away" and "oh shit". Apparently it's safe to operate your phone charger with 0.5mm paper & homeopathic enamel between your USB charger primary and secondary during thunderstorm whilst sitting in your shed connected via outdoor wiring, having your feet massaged via foot-massage bath, but a chunky multimeter (even DT830 Harbor Freight freebie is quite chunky in comparison) is a death trap.
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Where I live, a lot of electrical cabling is on the outside of the house: Garden lights, water pumps, pool pumps, air conditioning units. Often, 'house' electricians have to deal with those too.
If they are powered by power derived from an indoor distribution panel, then why they pose CAT4 hazard?
Of course, this is taking a risk since CAT3 doesn't require so high voltage transient seen by induced lightning, but let's face it, how big a chance will you be hit by an induced lightning over just a few meters of cable? Induced lightning protection is needed for long distance outdoor wires due to longer length, usually a few meters from service drop to your house. But for just a few meters from your panel to AC unit? I don't think there is a big chance.
The IEC is very influential. When the commission recommends something, it is usually adopted fairly quickly by most countries, sometimes with a few variations.
All IEC International Standards are fully consensus-based and represent the needs of key stakeholders of every nation participating in IEC work. Every member country, no matter how large or small, has one vote and a say in what goes into an IEC International Standard.
Close to 20 000 experts from industry, commerce, government, test and research labs, academia and consumer groups participate in IEC Standardization work.
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They pose CAT4 hazard, because person using a meter isn't qualified to discriminate between "lightning more than few kilometers away" and "oh shit". Apparently it's safe to operate your phone charger with 0.5mm paper & homeopathic enamel between your USB charger primary and secondary during thunderstorm whilst sitting in your shed connected via outdoor wiring, having your feet massaged via foot-massage bath, but a chunky multimeter (even DT830 Harbor Freight freebie is quite chunky in comparison) is a death trap.
False for several reasons:
a) Phone chargers don't have a range selector switch or other ways for people to mess it up and they're usually sealed so dirt can't get inside.
b) If you're an electrician poking around wires it often means you're modifying those wires. Not many people modify their phone chargers.
c) Joe has exploded several meters in his thread. He doesn't test on the current ranges.
Would yo also argue that your car doesn't need airbags because you're a perfect driver and the roads around your house are fine?
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Would yo also argue that your car doesn't need airbags because you're a perfect driver and the roads around your house are fine?
Nope, that's why things like circuit breakers and GFID/RCDs exist on low voltage.
c) Joe has exploded several meters in his thread. He doesn't test on the current ranges.
And working at a substation 15kV -> 400V I haven't exploded any.
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Would yo also argue that your car doesn't need airbags because you're a perfect driver and the roads around your house are fine?
Nope, that's why things like circuit breakers and GFID/RCDs exist on low voltage.
They won't prevent the meter from exploding in your hand if you select the wrong range.
c) Joe has exploded several meters in his thread. He doesn't test on the current ranges.
And working at a substation 15kV -> 400V I haven't exploded any.
Would you use a UT61E if you were working around substations every day?
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They pose CAT4 hazard, because person using a meter isn't qualified to discriminate between "lightning more than few kilometers away" and "oh shit". Apparently it's safe to operate your phone charger with 0.5mm paper & homeopathic enamel between your USB charger primary and secondary during thunderstorm whilst sitting in your shed connected via outdoor wiring, having your feet massaged via foot-massage bath, but a chunky multimeter (even DT830 Harbor Freight freebie is quite chunky in comparison) is a death trap.
Seriously , who said that it s safe playing around with electrical equipment while bathing your feet in water ? Every manual of electrical equipment said to keep it away from water and to disconnect from the mains at a thunderstorm .
But even it is connected to the same circuit with outdoor socket or directly connected equipment , the phone charger is connected in a socket , so the primary side is CAT II rated because of the contact resistance between the plug and the contact of the socket . The secondary side of the charger is 5 V almost so it is a low voltage device and CAT 0 rated according the rules so it is " safer" to poke around like in your example than measuring voltage with an unsafe meter
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I am wondering why are folks defaulting to thinking that I would be doing high voltage stuff... For me there is a voltage cap of 400Vrms on my projects (highest voltage in a mains-rated PFC circuit)
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I am wondering why are folks defaulting to thinking that I would be doing high voltage stuff...
Who said "high voltage"? I think everybody's talking about mains electricity.
For me there is a voltage cap of 400Vrms on my projects (highest voltage in a mains-rated PFC circuit).
I was about to say "don't use a Uni-T for that" then I remembered you've been using a DT890. A Uni-T is a big step up in safety.
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I am wondering why are folks defaulting to thinking that I would be doing high voltage stuff...
Who said "high voltage"? I think everybody's talking about mains electricity.
For me there is a voltage cap of 400Vrms on my projects (highest voltage in a mains-rated PFC circuit).
I was about to say "don't use a Uni-T for that" then I remembered you've been using a DT890. A Uni-T is a big step up in safety.
With the Fluke 87-V costing 20x more than the UT61E here I might stuck on that for a long while. But hey at least it have true RMS and computer connection features.
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My UT61E has drifted out on calibration DC volts. At 5.0V it reads ~ 4.6V....Now I have to get a precision voltage ref to fix it. Its only ~ 1yr old. Thing is now I don't trust it on other modes!
Might see if I can pick up a 2nd hand fluke but Australia is so expensive. Probably have to go to fleabay USA.
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For everyone recommending a Fluke: check the price. A UT61E in western market sells at $50, while a used Fluke 87V is only $220, but in China, UT61E only sells at $25, and a Fluke 87V sells at at least $285.
Now, instead of 4.4x the price, it is 11.4x the price difference.
...and will last 20x longer!
PS: http://www.ebay.com/sch/i.html?_nkw=fluke+101 (http://www.ebay.com/sch/i.html?_nkw=fluke+101)
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If you're over the Uni-Too good to be true thing, and can't afford a Fluke,
then hopefully a Jaycar or Altronics store is not far away..
They have some decent meters with warranties, at any price point you need,
but don't expect the $20 meter that looks the same as the $80 one, to work as well ;D.
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Hi gents Electro Detextive...yeah I have a qty of old Jaycar and DSE multimeters. Funny enough my old digetech QM-1525 holds better accuracy than the UniT.
I will have to get a cheap precision reference for now but I will be looking for a Fluke. Not the 17B+...although why not. Yes it was for China market but hey...the price. :-+
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If you're over the Uni-Too good to be true thing
The UT61E has some good points but writing "CAT IV 600V" on the front is hard to forgive.
Interestingly: There are some UT61Es with a much lower CAT rating stamped on them.
(https://www.eevblog.com/forum/testgear/how-good-is-the-ut61-series/?action=dlattach;attach=317549;image)
CAT II / low-end CAT III seems a lot closer to the truth.
I will be looking for a Fluke. Not the 17B+...although why not.
There's nothing wrong with the 17B+. It's not overloaded with features for the price but it's a very solid meter.
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Mine says:
CATV 600V
CATIII1000V
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BTW, I'm never a fan of F15B+ as it doesn't have uA measurement
Yes it does!
http://www.fluke.com/fluke/iden/digital-multimeters/general-purpose-multimeters/fluke-15b+.htm?pid=78680 (http://www.fluke.com/fluke/iden/digital-multimeters/general-purpose-multimeters/fluke-15b+.htm?pid=78680)
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Hi gents Electro Detextive...yeah I have a qty of old Jaycar and DSE multimeters. Funny enough my old digetech QM-1525 holds better accuracy than the UniT.
I will have to get a cheap precision reference for now but I will be looking for a Fluke. Not the 17B+...although why not. Yes it was for China market but hey...the price. :-+
If you want a cheap decent Fluke in oz, take a look at 114, 115, 116 and 117.
One of them may have the bare bone basics you need, or buy two with different features to cover all bases.
They go cheap used, a pair might set you back 200>250?
People flog them to buy 87Vs or orange eye candy battery slurping display jobs, or getting out of the trade.
My 114 does the no brainer front line stuff unless I need the 87V, or have both going.
fwiw I scored an unloved APPA 99111 which is nice and agrees with Fluke 87V in a side by side shootout,
and has Fluke style dual HRC fuses inside. You can get lower models cheap locally on Ebay sometimes (badged as Benning too) check the specs first!
BTW, all my 'decent' Jaycar meters I bought as Electro Noob are still kicking 20 years later, and up to spec
Cap meter, LCR, clamp, and a pair of $50 yellow peril multimeters (with transistor checker! lol) work great and won't be tossed any time soon.
Admittedly I have opened them all up and made sure they are 100% as they should be (no sweat shoppe production line oopsies)
The 3 Tandy/RS ones before them are probably still ok too, lost one to battery leakage BS ages ago |O
I keep all of them away from the mains unless necessary, and make sure I'm on the ball (no beer, and no phone rings from alien speak telemarketers about to get an unbelievable earful of insult HELL) >:D
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... you can buy a DMM check and calibrate your UT61E every year. It doesn't need fancy special software to calibrate, just trimmers.
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Is there a calibration procedure available for the UT61E?
:)
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Is there a calibration procedure available for the UT61E?
:)
No official ones, but you can play with pots randomly and see which does what.
Take a picture before touching anything so that you can fallback.
Here is an unofficial one: http://gushh.net/blog/ut61e-calibration/ (http://gushh.net/blog/ut61e-calibration/)
Thank you. That one talks about adjusting the VDC mode, and I think there was a thread about replacing VR1, again to adjust the VDC mode. In my case VDC seems to be spot on, it is the resistance mode that would benefit improvement.
I think, for now, I will keep searching.
:)
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... you can buy a DMM check and calibrate your UT61E every year. It doesn't need fancy special software to calibrate, just trimmers.
...
Is there a calibration procedure available for the UT61E?
:)
you calibrate it by throwing it against a concrete wall, and purchasing a fluke. :D
just kidding...
you can usually find a data sheet on a particular dmm chipset and use it to find out what the various trimmers adjust.
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i dont know why people keep talking about fluke meters like they last forever,
a friend has a few 77's
all needed new zebrastrip and one needed a new display glass.
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i dont know why people keep talking about fluke meters like they last forever,
a friend has a few 77's
all needed new zebrastrip and one needed a new display glass.
Flukes are nothing special, just like any other decent meter they last as long as you take care of them, and also depends on temperature and environmental conditions. I've replaced several zebra strips and couple LCD's on Flukes over the years. Also I've had a couple 80 series with brittle shit plastic with broken clips and standoffs. Fluke is somewhat overrated in my opinion, it's just another meter.
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you calibrate it by throwing it against a concrete wall, and purchasing a fluke. :D
just kidding...
I have several brands of multimeters, among them I have three Fluke. I am flying 50,000 feet above the "Fluke versus other brands" war ;)
you can usually find a data sheet on a particular dmm chipset and use it to find out what the various trimmers adjust.
Thank you for the tip, I will look into this.
:)
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i dont know why people keep talking about fluke meters like they last forever,
a friend has a few 77's
all needed new zebrastrip and one needed a new display glass.
Flukes are nothing special, just like any other decent meter they last as long as you take care of them, and also depends on temperature and environmental conditions. I've replaced several zebra strips and couple LCD's on Flukes over the years. Also I've had a couple 80 series with brittle shit plastic with broken clips and standoffs. Fluke is somewhat overrated in my opinion, it's just another meter.
I replaced a few zebra strips on them as well, but they were 15-20 years old or something. I have an old 87 (non V) that's probably 20 years old now, and still in spec.
I have some older Flukes like the 8060a which still work without any repairs (although should probably be recapped), and those are 30+ years old also still in spec.
The thing is Fluke meters are pretty great barring some exceptions, they are generally well built. In some instances the build quality could be better, but it's never downright cheap, they never just skimp on stuff. Features also tend to be well implemented. I mean, what year is it? And you still can't expect a fast latching continuity test from most DMMs?
Do they have the best build quality? Probably not, there are exceptions, but the quality is still pretty solid. Some Fluke meters have brass threads on all the screws (28II) some like the 87V don't. But most other meters don't either.
You also have to realize you're comparing 20+ old Flukes to today's meters. Plastics and manufacturing has gotten better since then.
The thing with Fluke however is that it's a known quantity, for the most part you know what you're getting, and there is a long track record of reliability, stability and sure some problems behind them.
That's not to say that an Agilent, Brymen, Metrahit.. won't get you something better for your needs, but Fluke's reputation is undeniable.
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Ok tested mu UT61E against 3 other multimeters I have (cannot find the 4th!)...
Urrrrgggghhh...my UT61E is way out on voltage. 9.1V @ 10V in. Ok granted I do not have a precision reference just a PSU with inbuilt meter, but the other meters are within .05 ~ .03V of 10V!
Damn I'll have to get a precision reference now! It should have not drifted that far out in a year!
edit:
Actually I purchased this in 2015!
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I just decided to measure my UT61E using the cheap ebay AD584 reference.
"2.498"
"4.998"
"7.497"
"9.996"I had recorded the values in May 2015 (so 2 years ago).. and it hadn't drifted at all, like not a single digit. Pretty impressive actually.
Same reference on my KEI2015
"2.50047"
"5.00087"
"7.50063"
"10.00027"
I do have to say though, I never use my UT61E. It just sits in one of the bins in case I want to use its logging capability. So this is with barely any use between measurements.
Also as I mentioned I do really like its form factor. Small and very sturdy on the bench, also the screen is great.
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i suspect it's not "drift" but being bumped around causing the multi-turn preset to shift a bit.
those things arent the most stable devices.
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i suspect it's not "drift" but being bumped around causing the multi-turn preset to shift a bit.
those things arent the most stable devices.
It's likely mechanical stress related as you put it.
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i suspect it's not "drift" but being bumped around causing the multi-turn preset to shift a bit.
those things arent the most stable devices.
Quite possibly...
A bit of nail polish fixes that... LOL
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I wonder how good a reference some used ADR02B and ADR03B are. Maybe I can perform routine calibration use those.
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Is there a calibration procedure available for the UT61E?
:)
Just turn the big blue pot until it agrees with something known.
Urrrrgggghhh...my UT61E is way out on voltage. 9.1V @ 10V in. Ok granted I do not have a precision reference just a PSU with inbuilt meter, but the other meters are within .05 ~ .03V of 10V!
eg. Three other meters that are in agreement over a voltage.
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Ahh huh...just touched the voltage cal pot...it jumped big jump back to 9.99...volts on 10V in.
Now varying the wiper up/dwn it appears ok and changes accordingly (linear fashion) but at first it jumped ....a lot. Possible pot issue?
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Ahh huh...just touched the voltage cal pot...it jumped big jump back to 9.99...volts on 10V in.
Now varying the wiper up/dwn it appears ok and changes accordingly (linear fashion) but at first it jumped ....a lot. Possible pot issue?
Have a look at the solder joints holding it to the board before blaming the pot.
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Ahh huh...just touched the voltage cal pot...it jumped big jump back to 9.99...volts on 10V in.
Now varying the wiper up/dwn it appears ok and changes accordingly (linear fashion) but at first it jumped ....a lot. Possible pot issue?
Have a look at the solder joints holding it to the board before blaming the pot.
+1, most of the cases I found are cold joins, just watch carefully if the solder is shiny or hazy (cold join).
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Many thanks gents....took it apart touched up solder joins. They look ok under 3X loupe but they are shiner with 63/37 solder. It appears ok now, wiggling the pot before doing the joints didn't make any change but as said I redid them anyway.
Oh had a scare....put it back together temporarily held battery on meter...no display...re-did this all another 2 times...then realised the elastometric carbon strip was not clamped down by the PCB screws...urrrgh! :palm:
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Ahh huh...just touched the voltage cal pot...it jumped big jump back to 9.99...volts on 10V in.
Now varying the wiper up/dwn it appears ok and changes accordingly (linear fashion) but at first it jumped ....a lot. Possible pot issue?
Have a look at the solder joints holding it to the board before blaming the pot.
+1, most of the cases I found are cold joins, just watch carefully if the solder is shiny or hazy (cold join).
It's all shit lead free solder which is not shiny...
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Many thanks to all. I had noticed the meter getting really bad on accuracy in volts since the autumn cold weather arrived.
I fired it up this morning...spot on accuracy.
I'm not a meter man...I just use them.... they work or I get Peeved off! Once again thanks she's all good now. :-DMM
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Many thanks to all. I had noticed the meter getting really bad on accuracy in volts since the autumn cold weather arrived.
there is a fix for that.
http://forum.eepw.com.cn/thread/239953/1 (http://forum.eepw.com.cn/thread/239953/1)
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Hmmm its a $6 IC in Aust. Going to have to look at this. Noticed they have this IC in .1% and .05%! But the .05% is ~$6.
I'm not a meter man...but hey I'll try anything once....well almost anything! Had to laugh...typing in LT 1970 into browser ( I mistakenly left a space between terms) found "Mutiny on the Bounty"! What's that....your multimeter is not accurate...your going to modify it...Mutiny I say :-DD
I'll look at this and get back. Thanks
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Hmmm its a $6 IC in Aust. Going to have to look at this. Noticed they have this IC in .1% and .05%! But the .05% is ~$6.
and that's probably why it was not fitted - that's a lot of money in china!
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Hmmm its a $6 IC in Aust. Going to have to look at this. Noticed they have this IC in .1% and .05%! But the .05% is ~$6.
and that's probably why it was not fitted - that's a lot of money in china!
nah, they buy used fake ones on the black market... ;)
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I just imagine myself an electrician with a sadomaso rubber suit in a technical room >:D :-DD :palm:
You made me laugh so much it brought tears to my eyes. :-DD :-DD :-DD
3DB
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Just a question...modifying the Vref to an LT1790 hi precision...they don't explain (in the part pdf or above site) if they use 1% or better resistors and high precision caps?
I guess at least 1% would be required...or is this overkill.
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They won't prevent the meter from exploding in your hand if you select the wrong range.
That's why we don't use meters with possible low impedance path on high energy circuits unless we check twice or more we're on right range. No HRC fuse or CAT rating will help even on low voltage distribution line if you're near the transformer and something goes really wrong - I put my safety into considerations about other, more probable things, like knowing that if something goes wrong I won't fall down from the pole and have a head trauma (most electricity injures come not from an actual eletrical shock, but blunt trauma after you did nasty landing fom the ladder/whatever).
c) Joe has exploded several meters in his thread. He doesn't test on the current ranges.
And working at a substation 15kV -> 400V I haven't exploded any.
Would you use a UT61E if you were working around substations every day?
[/quote]
Yes, I would, to check why the light is out in the building. No other reason to use a multimeter in that environment;) Other things are measured via current transfomers and so on connected to separate meters so no reason or need to poke around. I must admit, it' s a bad example;)
But there is a device that will make most CAT focused people cringe. Incandescent bulb with two probes attached. It's still very useful - RCD tester, phase to earth voltage checker or phase-to-phase (you have to do it quick, as eg 230V bulbs don't like 400V for a long ime) and it loads the circuit well enough to get rid of any ghost voltages that LoZ option on DMM won't cover. I'm yet to see voltage stick that will draw 100W or so.
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Just a question...modifying the Vref to an LT1790 hi precision...they don't explain (in the part pdf or above site) if they use 1% or better resistors and high precision caps?
I guess at least 1% would be required...or is this overkill.
For most people, a DMM is only used in an indoor environment where temperature is in a narrow range. Therefore, tempco can be ignored. In that case, 1% or 10% doesn't make any difference if there is a trimming pot.
Is that based on your personal experience of the entire world population of handheld meters? I will say that I have never taken my 34401 into the field, but for handhelds I would guess until recently the vast majority of the time the meter is used outside the house. It gets a fair amount of heat cycling in the trailer and garage. Still, I don't need anything much beyond the free meters from Harbor Freight for this work so temperature is little concern. If they had a backlight and temperature input, I would be golden...
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blueskull...it gets quite cold (down to 0ºC and below) and hot (40ºC) here. Used indoors home work area, temp is around 15ºC ~ 25ºC.
Really if its accurate to .01Volt on low range then I'm happy. ATM its behaving much better since I re-worked the pot joins. If it stays this way then I'll probably leave it.
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I tested my UNI-T 61E between 20°C and 36°C by leaving it on in a PS foam box with a incandescent lamp for a few hours, connecting it to an external voltage reference
In spite of what I expected the value displayed never changed, although it was lower than the value displayed by a better multimeter
I tried to calibrate it via the inner voltage calibration trimmer and realized it is real crap
if you turn it 360° there is no change
then another few degrees of rotation and the value suddenly changes a lot
I should replace it with a new bourns trimmer
I just wonder if the crappy trimmer variation with temperature casually compensates the variation of the multimeter reference :-//
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......I tried to calibrate it via the inner voltage calibration trimmer and realized it is real crap ...if you turn it 360° there is no change..then another few degrees of rotation and the value suddenly changes a lot
I should replace it with a new bourns trimmer
That is exactly what I initially saw. Then winding the pot back and fourth...it started to give a more linear response. Quite odd like the wiper was stuck or not tracking correctly. Its keeping better voltage accuracy now though.
I also noted my PCB layout is different to the PCB in the Vref mod. The layout on mine is different and there is no unused pads for an LT1790 etc
The Pot on mine is "X202" so a 2K ohm pot multi-turn. The cct diagrams show it to be 1K ohm
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That is exactly what I initially saw. Then winding the pot back and fourth...it started to give a more linear response. Quite odd like the wiper was stuck or not tracking correctly. Its keeping better voltage accuracy now though.
Those trimmers use a really, really soft carbon for the track. The wipers gunk up fast.
(they're usually only rated for 200 adjustments!)
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I tested my UNI-T 61E between 20°C and 36°C by leaving it on in a PS foam box with a incandescent lamp for a few hours, connecting it to an external voltage reference
In spite of what I expected the value displayed never changed, although it was lower than the value displayed by a better multimeter
I tried to calibrate it via the inner voltage calibration trimmer and realized it is real crap
if you turn it 360° there is no change
then another few degrees of rotation and the value suddenly changes a lot
I should replace it with a new bourns trimmer
I just wonder if the crappy trimmer variation with temperature casually compensates the variation of the multimeter reference :-//
I would expect for 16 degree you would see 5.125 uV/degC or 82uV. Basically 8 counts. For all I know you were in the DCV range. I did not save my data and tc may not be linear. After temperature compensating mine with a diode/resistor, tc was 0.625uV/degC.
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I also noted my PCB layout is different to the PCB in the Vref mod. The layout on mine is different and there is no unused pads for an LT1790 etc
damn, i have to check mine later!!
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......I tried to calibrate it via the inner voltage calibration trimmer and realized it is real crap ...if you turn it 360° there is no change..then another few degrees of rotation and the value suddenly changes a lot
I should replace it with a new bourns trimmer
That is exactly what I initially saw. Then winding the pot back and fourth...it started to give a more linear response. Quite odd like the wiper was stuck or not tracking correctly. Its keeping better voltage accuracy now though.
I also noted my PCB layout is different to the PCB in the Vref mod. The layout on mine is different and there is no unused pads for an LT1790 etc
The Pot on mine is "X202" so a 2K ohm pot multi-turn. The cct diagrams show it to be 1K ohm
mine is 2kohm too
I made as you advised and was able to trim it closer to (what is supposed to be) the real voltage :)
now it is still low on ohm reading but anyway I have better multimeters for that purpose
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I tested my UNI-T 61E between 20°C and 36°C by leaving it on in a PS foam box with a incandescent lamp for a few hours, connecting it to an external voltage reference
In spite of what I expected the value displayed never changed, although it was lower than the value displayed by a better multimeter
I tried to calibrate it via the inner voltage calibration trimmer and realized it is real crap
if you turn it 360° there is no change
then another few degrees of rotation and the value suddenly changes a lot
I should replace it with a new bourns trimmer
I just wonder if the crappy trimmer variation with temperature casually compensates the variation of the multimeter reference :-//
I would expect for 16 degree you would see 5.125 uV/degC or 82uV. Basically 8 counts. For all I know you were in the DCV range. I did not save my data and tc may not be linear. After temperature compensating mine with a diode/resistor, tc was 0.625uV/degC.
I guess I've just been lucky as I checked the multimeter reading various times during the test and it didn't show any variation apart flipping the last digit at the end
I used a seasoned AD588BQ V reference with 0.1% 15ppm resistors to bring the voltage down around 1.5V
so I think the variation is no more than 1 part per 10000 over 20 to 35°C
of course I cannot say anything about drift in other voltage ranges
BTW during that time I've also checked the 1.5V reference (both the reference and the other DMM at ambient temperature) with a Brymen 867S and it showed no drift