NEW $50 multimeter shootout - 15 DMMs compared - Aug 2, 2015

[5ky]

Good video.  As long as the meters are just sitting there, maybe you could verify that all of the functions still work, not just the AC volts and run them at the same line voltage Dave does.

I will verify that each works tonight.  (a few had some rattles after the drop tests)  I wish I had an easy way to test with 240 vac without going to the breaker box

[Lightages]

Easier and safer would be to use a transformer. You can also use a variac, not as safe. That is if you have one or the other.

[5ky]

Easier and safer would be to use a transformer. You can also use a variac, not as safe. That is if you have one or the other.

Aren't variacs generally step down?  I wasn't aware you could get ones that are wound to go higher than the input.  If so, I need to do some shopping tonight!

[retrolefty]

Easier and safer would be to use a transformer. You can also use a variac, not as safe. That is if you have one or the other.

Aren't variacs generally step down?  I wasn't aware you could get ones that are wound to go higher than the input.  If so, I need to do some shopping tonight!

 Some variacs ranged 0-100% of the input AC voltage. However popular also were tapped primary where the secondary would range like 0-125% because the input AC was applied between one end and the tap lower from the other end of the winding.

[Lightages]

With care, and I mean extreme care, you can use a variac backwards. You have to pay attention and understand the risks, but it can be done. You need to not exceed the VA rating and pay special attention that you don't turn the dial too far and basically cause a short on the variable tap while using it as an input. It would be best to put a fuse in line with the variable tap before using it as an input.

And read my words again, EXTREME CARE. This is not a very safe thing to do.

[joeqsmith]

Don't buy anything just to run this test.  I can run them at 220 or whatever.   It would be interesting to hear if they all do still work.  No need to make another video, just a quick test.     

Also, I am not sure if it matters but when I ran these tests, I would run the meters through all of their modes.   For example, diode continuity resistance may be on one switch setting, so I would cycle through them.   My thinking was the the input protection may behave differently for the various modes. 

[5ky]

Don't buy anything just to run this test.  I can run them at 220 or whatever.   It would be interesting to hear if they all do still work.  No need to make another video, just a quick test.     

Also, I am not sure if it matters but when I ran these tests, I would run the meters through all of their modes.   For example, diode continuity resistance may be on one switch setting, so I would cycle through them.   My thinking was the the input protection may behave differently for the various modes.

I went back and ran them all on each individual range on mains to be sure.  I'm about to test each meter to see if they took any damage and then I'll cut and upload the drop tests and final results tonight.  I heard a few rattles after the drops, but I think those are fuses that popped out, but we shall see!

[joeqsmith]

found it
thanks again joeqsmith for his experiments and of interest to me n some others is the surge generator

and when i first saw this video title i thought he was using some kind of HV gadget to arc a HV inside the meter and PWM the HV to play music, but it was the continuity test ~!

Glad you enjoyed them.  I started out thinking I would just make the UNI-T play a single tone, lame song.   The problem is that it wants to beep at at a fixed frequency.   However, if you keep the pulses short enough it does not actually make the beep and you get more of a click.  I just high passed, zero crossed, then one-shot.   

Making your own generator is not a big deal.   Take a cap, charge it up, then touch it across something conductive.  Instant transient generator....   If you want more energy, bigger caps and/or more voltage....  Shaping the waveform may require some Rs and Ls.   Maybe a C or two.   Cap discharge rates may be a concern.  Need the right parts for the job.    Parts that make up the output network need to be sized.   I over drove everything in the first generator.  I never intended to use it for very long.   Damaged more than one part playing with it.   I showed what was left of a carbon resistor in one video that had been part of the output network.  Not burned, but shattered.      So maybe some sort of box is a good idea to catch the flying debris.   I would maybe check some sort of safety guidelines.   It only took 10J to do in every meter except the 101.    Dave had a video where they were hitting them with 400J or so.  Meters were coming apart.   Fun, but was more looking to see how they stacked against each other.   Hard to do if they are all damaged in the first hit.   

Don't buy anything just to run this test.  I can run them at 220 or whatever.   It would be interesting to hear if they all do still work.  No need to make another video, just a quick test.     

Also, I am not sure if it matters but when I ran these tests, I would run the meters through all of their modes.   For example, diode continuity resistance may be on one switch setting, so I would cycle through them.   My thinking was the the input protection may behave differently for the various modes.

I went back and ran them all on each individual range on mains to be sure.  I'm about to test each meter to see if they took any damage and then I'll cut and upload the drop tests and final results tonight.  I heard a few rattles after the drops, but I think those are fuses that popped out, but we shall see!

Sounds good.  Looking forward to your results.

Time to wind some sort of coil.

[Muxr]

Nice job @5ky. Really well done series of reviews.

[5ky]

Took me a month, but I finally got it all done.  The drop tests video is uploaded and viewable now: (but still processing for the higher resolutions):

The slow motion shots turned out great for being in a dark garage and being recorded by an iPhone 

[Lightages]

Thanks for the videos. I would like to point out one thing if I may. The IEC tests are for a drop to a hard wood floor, not concrete, if I remember correctly. But this shows at least a fairly consistent test between models.

[5ky]

Thanks for the videos. I would like to point out one thing if I may. The IEC tests are for a drop to a hard wood floor, not concrete, if I remember correctly. But this shows at least a fairly consistent test between models.

While I do have oak floors in my kitchen/dining rooms--my wife would murder me if I did the drop tests on them 

EDIT: This makes me wonder why they chose wood for their testing.  I wonder if it's the most common floor type that multimeters would face in the real world?

[saturation]

Many physical and environmental toughness tests are offshoots from US military requirements, i.e., MILSPEC.   There are many drop tests but most have to do with quantifying the amount of shock [e.g. newtons ] and the shape of the curve from the response.  For hand helds, IIRC, drop tests are multiple times each corner, top, back, and face of device.

Military tests test suitability when dropped or shaken around a wooden crate, say it came loose from its mounting, drop to a wooden floor by a user as field deployment barracks have wooden, dirt or sand floors, and drop by something like a parachute.

I'm not sure why the drop onto wood floors translated to suitability for civilians onto concrete or tiled floors, maybe its because during testing on wood its done 20+ times. 

[Meter Junkie]

Nice job 5KY.

A couple of comments.

While I applaud all the testing you did, I did not expect any failures on mains up to 120V. I also would not expect any up to 240V.  But, over 240V, I would expect some. I once had a Uni-Trend meter that did have PTC protection on the front end to handle Mains. But, when I looked it up, it was rated to 250V. If any of those meters have these 250V PTC's, they should all handle your testing, but may not be able to go to the 600V they are supposed to.

For the drop testing, I agree that it was supposed to be to wood, but that does not mean using your wood floors. All you would need is a piece of plywood that you lay on the concrete. I watched some Fluke videos where the wood was just laying on the floor, and you could see it bounce up when a meter hit it. I also saw some Klein videos where they are dropping to steel, and the steel is not a flat surface, which is about as tough as you can get to pass. But, they are using that to go beyond the standard. They even have a video that they drop a meter 40 feet from a bucket truck onto pavement.

I agree that losing the fuses at 3 feet seems bad. I would think all meters should be able to handle that. The B&K case breaking really surprised me. I expected better from them.

[5ky]

Nice job 5KY.

A couple of comments.

While I applaud all the testing you did, I did not expect any failures on mains up to 120V. I also would not expect any up to 240V.  But, over 240V, I would expect some. I once had a Uni-Trend meter that did have PTC protection on the front end to handle Mains. But, when I looked it up, it was rated to 250V. If any of those meters have these 250V PTC's, they should all handle your testing, but may not be able to go to the 600V they are supposed to.

For the drop testing, I agree that it was supposed to be to wood, but that does not mean using your wood floors. All you would need is a piece of plywood that you lay on the concrete. I watched some Fluke videos where the wood was just laying on the floor, and you could see it bounce up when a meter hit it. I also saw some Klein videos where they are dropping to steel, and the steel is not a flat surface, which is about as tough as you can get to pass. But, they are using that to go beyond the standard. They even have a video that they drop a meter 40 feet from a bucket truck onto pavement.

I agree that losing the fuses at 3 feet seems bad. I would think all meters should be able to handle that. The B&K case breaking really surprised me. I expected better from them.

Turns out, the BK wasn't broken.  Fuse popped out and the 10amp input jack sleeve popped loose and wedged the corner of the chassis open.  Once I used pliers to get the input jack plastic sleeve back into place, as well as the fuse, it reassembled back to normal.  Not acceptable for a 1M drop, but it technically didn't break.

[saturation]

5ky, thanks for all the good work.  I agree with Meter Junkie's critique, but your test was very informative since all the meters were given the same treatment.

Technically, I think meters with popped off fuses failed the drop test.  IIRC the procedure, meters are inspected for hazards and subjected to a voltage withstand test after the drop, and had the inspection not found fuses had dislodged, it would easily cause some events during a voltage test.  The voltage test could reveal subtle breaks, such as trace cracks, that could be missed visually.

A meter falling off a table or a ladder is fairly common, particularly doing a setup just before probing, particularly in marked hazards in the testing environment.  If the fuses didn't make a sound yet dislodged, that's most concerning. 

[5ky]

5ky, thanks for all the good work.  I agree with Meter Junkie's critique, but your test was very informative since all the meters were given the same treatment.

Technically, I think meters with popped off fuses failed the drop test.  IIRC the procedure, meters are inspected for hazards and subjected to a voltage withstand test after the drop, and had the inspection not found fuses had dislodged, it would easily cause some events during a voltage test.  The voltage test could reveal subtle breaks, such as trace cracks, that could be missed visually.

A meter falling off a table or a ladder is fairly common, particularly doing a setup just before probing, particularly in marked hazards in the testing environment.  If the fuses didn't make a sound yet dislodged, that's most concerning.

Definitely.  I think they should mold something on the other side of the chassis that nearly touches the fuse so that while the chassis is assembled, the fuses can't go anywhere.  It would be simple to implement and effective.

As for testing with 240vac and on wood--I just emulated the benchmark: Dave's shootouts.  (only I don't "easy" access to 240 vac)

I figured if I copy the things he tests, it'll be easier to compare meters that I reviewed versus the ones he reviewed. 

Unrelated note: I noticed that tester.co.uk had the hioki dt4282 for cheaper than I've seen it anywhere and had a moment of weakness.  (it arrives tomorrow)

[Robomeds]

5ky, thanks for all the good work.  I agree with Meter Junkie's critique, but your test was very informative since all the meters were given the same treatment.

Technically, I think meters with popped off fuses failed the drop test.  IIRC the procedure, meters are inspected for hazards and subjected to a voltage withstand test after the drop, and had the inspection not found fuses had dislodged, it would easily cause some events during a voltage test.  The voltage test could reveal subtle breaks, such as trace cracks, that could be missed visually.

A meter falling off a table or a ladder is fairly common, particularly doing a setup just before probing, particularly in marked hazards in the testing environment.  If the fuses didn't make a sound yet dislodged, that's most concerning.

Definitely.  I think they should mold something on the other side of the chassis that nearly touches the fuse so that while the chassis is assembled, the fuses can't go anywhere.  It would be simple to implement and effective.

As for testing with 240vac and on wood--I just emulated the benchmark: Dave's shootouts.  (only I don't "easy" access to 240 vac)

I figured if I copy the things he tests, it'll be easier to compare meters that I reviewed versus the ones he reviewed. 

Unrelated note: I noticed that tester.co.uk had the hioki dt4282 for cheaper than I've seen it anywhere and had a moment of weakness.  (it arrives tomorrow)

I think many do.  However, some like the Uni-T's clearly are designed for more than one fuse type.  The direct from China models seem to feature really small fuses while the retail for Europe models often have larger fuses.  I've also seen this in some Brymens.  A while back I did a tear down on a Brymen/Amprobe AM120 ( https://www.eevblog.com/forum/testgear/amprobe-%28bryman%29-am130-teardown/msg311314/#msg311314 ).  Anyway, it used smaller fuses vs the larger bus sized ones like you see in a Fluke 87.  The case was clearly designed to handle both types as shown in this AM270 tear down ( https://www.eevblog.com/forum/testgear/teardown-amprobe-am-270-digital-multimeter/msg70056/#msg70056 ).  I did see that my Fluke 187 does have plastic ribs above the fuses to keep them in place. 

[5ky]

5ky, thanks for all the good work.  I agree with Meter Junkie's critique, but your test was very informative since all the meters were given the same treatment.

Technically, I think meters with popped off fuses failed the drop test.  IIRC the procedure, meters are inspected for hazards and subjected to a voltage withstand test after the drop, and had the inspection not found fuses had dislodged, it would easily cause some events during a voltage test.  The voltage test could reveal subtle breaks, such as trace cracks, that could be missed visually.

A meter falling off a table or a ladder is fairly common, particularly doing a setup just before probing, particularly in marked hazards in the testing environment.  If the fuses didn't make a sound yet dislodged, that's most concerning.

Definitely.  I think they should mold something on the other side of the chassis that nearly touches the fuse so that while the chassis is assembled, the fuses can't go anywhere.  It would be simple to implement and effective.

As for testing with 240vac and on wood--I just emulated the benchmark: Dave's shootouts.  (only I don't "easy" access to 240 vac)

I figured if I copy the things he tests, it'll be easier to compare meters that I reviewed versus the ones he reviewed. 

Unrelated note: I noticed that tester.co.uk had the hioki dt4282 for cheaper than I've seen it anywhere and had a moment of weakness.  (it arrives tomorrow)

I think many do.  However, some like the Uni-T's clearly are designed for more than one fuse type.  The direct from China models seem to feature really small fuses while the retail for Europe models often have larger fuses.  I've also seen this in some Brymens.  A while back I did a tear down on a Brymen/Amprobe AM120 ( https://www.eevblog.com/forum/testgear/amprobe-%28bryman%29-am130-teardown/msg311314/#msg311314 ).  Anyway, it used smaller fuses vs the larger bus sized ones like you see in a Fluke 87.  The case was clearly designed to handle both types as shown in this AM270 tear down ( https://www.eevblog.com/forum/testgear/teardown-amprobe-am-270-digital-multimeter/msg70056/#msg70056 ).  I did see that my Fluke 187 does have plastic ribs above the fuses to keep them in place.

I suppose a piece of foam would work too, to accommodate for the different size fuse situation.  Anything would be better than fuses popping out like that from a 1M drop.

This makes me want to go take all my meters apart to see if any of them have something on the other end of the chassis to hold the fuse in place.

[Robomeds]

Yeah, I don't look at 1m as that far.  I know Motorola's old cell phones were rated at 1.8M to concrete (it was OK for the battery and door to come off if they could be put back on).  I generally expect 1m (at least to wood) to function the whole time. 

[saturation]

Its safer to mold a piece of rigid ABS plastic stuck on the opposite section of the case right atop the fuses to keep them from popping out, foam could melt or burn with heat, or it will deform with age and lose it compressive quality.

For 240Vac, the typical source in most US homes are large appliances, wash dryers, heat pumps etc., if they are plugged in.  They are NEMA 10-30R sockets, the setup is 120V, Ground, 120V.  Note you are in CAT III territory therein so work safe.


 

[joeqsmith]

Watched the last video.  Job well done.  I am not sure why they don't use better fuse holders.  That thin stamped crap bends pretty easy and takes a set.    Picture shows the ones I used to replace the junk in the Mastech.  They cause the fuse sit up a little higher but did not interfere with the back cover.   

So everything worked in all the modes.   I guess I too am not surprised.   Even if you ran them at 220, I doubt there would be any problems.   I ran a few on a 600ish volt DC supply and the ones I tested did not pull a lot of current.     

[5ky]

A few of them had decent fuse holders but it seemed the majority used the really weak ones similar to the ones that failed from the drop.

The only 230 plug I have in my home is behind my dryer, and I'm far too lazy to pull it out just for testing the meters 

[joeqsmith]

A few of them had decent fuse holders but it seemed the majority used the really weak ones similar to the ones that failed from the drop.

The only 230 plug I have in my home is behind my dryer, and I'm far too lazy to pull it out just for testing the meters 

No problem.  I am thinking to add some sort of built-in bias supply to the new generator. Started out thinking of just using a transformer but now I am thinking of some sort of ARB that can do +/-KV sort of thing.    Lot's of different ideas but still focusing on proving out the basic parts.    Have made a little progress.   I'll post a video of it sometime today.   

[5ky]

A few of them had decent fuse holders but it seemed the majority used the really weak ones similar to the ones that failed from the drop.

The only 230 plug I have in my home is behind my dryer, and I'm far too lazy to pull it out just for testing the meters 

No problem.  I am thinking to add some sort of built-in bias supply to the new generator. Started out thinking of just using a transformer but now I am thinking of some sort of ARB that can do +/-KV sort of thing.    Lot's of different ideas but still focusing on proving out the basic parts.    Have made a little progress.   I'll post a video of it sometime today.   

I saw the video today and it looks like it's going to be a pretty flexible little rig!