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Online technix

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How good is the UT61 series?
« on: May 19, 2017, 06:48:04 PM »
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?
 

Offline The Soulman

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Re: How good is the UT61 series?
« Reply #1 on: May 19, 2017, 08:55:25 PM »
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.
No point in making a point just to make a point, that would be pointless.
 
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Offline Fungus

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Re: How good is the UT61 series?
« Reply #2 on: May 19, 2017, 09:29:11 PM »
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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Offline sibeen

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Re: How good is the UT61 series?
« Reply #3 on: May 19, 2017, 10:08:40 PM »


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.
 

Offline Fungus

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Re: How good is the UT61 series?
« Reply #4 on: May 19, 2017, 10:21:16 PM »
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:



« Last Edit: May 19, 2017, 11:48:48 PM by Fungus »
 

Offline Fungus

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Re: How good is the UT61 series?
« Reply #5 on: May 19, 2017, 10:37:11 PM »
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.

http://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/

 

Offline Muxr

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Re: How good is the UT61 series?
« Reply #6 on: May 20, 2017, 12:38:42 AM »
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.
 

Offline Fungus

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Re: How good is the UT61 series?
« Reply #7 on: May 20, 2017, 01:15:18 AM »
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.
 

Offline rstofer

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Re: How good is the UT61 series?
« Reply #8 on: May 20, 2017, 01:51:10 AM »
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

I like:

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

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

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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Offline Wytnucls

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Re: How good is the UT61 series?
« Reply #9 on: May 20, 2017, 02:19:50 AM »
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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Offline Fungus

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Re: How good is the UT61 series?
« Reply #10 on: May 20, 2017, 02:29:40 AM »
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:
 

Offline WackyGerman

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Re: How good is the UT61 series?
« Reply #11 on: May 20, 2017, 04:32:27 AM »
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
 

Offline SkyMaster

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Re: How good is the UT61 series?
« Reply #12 on: May 20, 2017, 10:31:40 AM »
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.

 :)
 

Online mariush

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Re: How good is the UT61 series?
« Reply #13 on: May 20, 2017, 10:35:28 AM »
Quote
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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Offline sibeen

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Re: How good is the UT61 series?
« Reply #14 on: May 20, 2017, 10:42:34 AM »


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.
 

Offline SkyMaster

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Re: How good is the UT61 series?
« Reply #15 on: May 20, 2017, 10:59:44 AM »
Quote
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.

 :)
 

Offline joeqsmith

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Re: How good is the UT61 series?
« Reply #16 on: May 20, 2017, 11:14:08 AM »
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. 
How electrically robust is your meter?? http://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Online stj

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Re: How good is the UT61 series?
« Reply #17 on: May 20, 2017, 12:17:43 PM »
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.
« Last Edit: May 20, 2017, 12:21:54 PM by stj »
 

Offline Fungus

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Re: How good is the UT61 series?
« Reply #18 on: May 20, 2017, 06:38:28 PM »
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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Offline Trakehner1

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Re: How good is the UT61 series?
« Reply #19 on: May 20, 2017, 06:46:14 PM »
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...
 

Offline Fungus

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Re: How good is the UT61 series?
« Reply #20 on: May 20, 2017, 06:50:54 PM »
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:
 

Offline joeqsmith

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Re: How good is the UT61 series?
« Reply #21 on: May 21, 2017, 03:36:18 AM »
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
How electrically robust is your meter?? http://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline kcbrown

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Re: How good is the UT61 series?
« Reply #22 on: May 21, 2017, 12:47:44 PM »
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
 

Offline joeqsmith

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Re: How good is the UT61 series?
« Reply #23 on: May 21, 2017, 12:49:18 PM »
That was a conservative estimate!
How electrically robust is your meter?? http://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline kcbrown

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Re: How good is the UT61 series?
« Reply #24 on: May 21, 2017, 02:56:41 PM »
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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