Handheld meter robustness testing - Page 1
Forum section: electronics / testgear

author: joeqsmith
author_rank: Super Contributor
timestamp: June 06, 2015, 12:54:30 am
content: The latest spreadsheet is now available on GoogleDocs here:https://docs.google.com/spreadsheets/d/1cXzYpIoyVm9QJUju4KXqM22CEQZP3_xwWvDyeVwxTy4/edit?usp=sharingAnswers to Frequently Asked Questions may be found here:https://docs.google.com/document/d/1gEPFeOZpsNSm0-7sA98w2P5XE5x77Oal9dQEYvQnF6g/edit?usp=sharingBecause the generator used for these tests changed from the first round to the second, it is difficult to correlate the data. The UNI-T UT90A that was used in the first round had been repaired and tested again in the second round. You will notice that while it survived a 3.2KV 2 ohms pulse in the first round, it fails at 1.5KV 2 ohm during the second round. This is because the pulse width on the new generator was increased by a fair amount to more closely represent the IEC standard.You will also note that the AM530 did not make it as far into the tests at the AM510 did in the first round. Some of the meters that 5KY provided me with were a much higher grade.Because the generator used in the first round of testing had to be rebuilt for each test ran, when the Fluke 87V was finally tested we only knew it was not as robust as the winner of the $50 shootout, the Fluke 101. During the second round, enough people had asked me about the 87V that I went ahead and reran one and was amazed that it did so poorly.I have very few rules when it comes to leaving comments on my YT channel.1) Don't personally insult anyone. Me or otherwise.2) Don't use my channel to post ads. I don't run ads and don't ask for donations. I am not making any money by posting this content. For you to try and profit from my efforts is in very poor taste.3) Don't ask about how to modify a meter or how to construct a transient generator like I show. Also, don't attempt to post lists of materials and don't try to tell others how to modify their meter. If I ignored you, you should be fine. If you are persistent most likely you will get banned. There are many concerns when it comes to working with higher voltages and currents, even at the levels I show in the videos.I have YT filters setup. If really don't care if your vocabulary is limited but the filters are fairly effective at picking up people who are intent on breaking the first rule. Just be aware they are being used.If you want to post about my channel to others, please don't post false statements about the tests I am running. Obviously I don't have any control over this. I am just asking that if you don't understand the tests being ran, maybe just point them to the FAQs and call it good.If the above rules bother you and you feel you can't follow them, please feel free to unsubscribe.Thanks.Table of ContentsFirst attempts at designing a waveform generatorhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg688021/#msg688021Selecting the first set of $50 USD meters to runhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg688363/#msg688363Initial testing of the waveform generatorhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg688607/#msg688607The first set meters have arrived and round I of the testing beginshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg695530/#msg695530Home made high voltage attenuatorhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg696093/#msg696093Fuses are now banned from testing and the low energy levels are explainehttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg697304/#msg697304From here on, its always a 2 ohm source....https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg697665/#msg697665The UNI-T UT139C shows up late from China.https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg698362/#msg698362Member Meter Junkie shows off their surge generatorhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg699353/#msg699353First set of $50 meters, Semi Finalshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg699631/#msg699631The UNI-T UT139C joins the remaining four meters and is damagedhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg699833/#msg699833First set of $50 meters, Finalshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg701147/#msg701147Member Meter Junkie runs a second Fluke 101 on their IEC combo generator at 12KVhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg703553/#msg703553I push the Fluke 101 to 13KV 100us FWHHhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg704183/#msg704183Hackaday runs a story on the testinghttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg705738/#msg705738The first of the higher cost meters, the Fluke 87Vhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg708183/#msg708183Member TechnologyCatalyst(5KY) steps into the game with a Round II of metershttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg746543/#msg746543Designing a programmable transient generatorhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg748162/#msg748162Testing the new transient generatorhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg763288/#msg763288Testing the second set of meters, Round 1https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg769212/#msg769212Testing the second set of meters, The Finalshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg777164/#msg777164Statisticshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg779711/#msg779711Rebuilding the generator (20KV, 50us FWHH), the Fluke 107 is pushed to its limithttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg780700/#msg780700UNI-T UT90A plays musichttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg782212/#msg782212Designing the half cycle AC line simulatorhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg789734/#msg789734Initial testing of the Half cycle AC line simulatorhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg795033/#msg795033The Fluke 17B+ Reviewhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg811544/#msg811544A second UNI-T UT139C is testedhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg815680/#msg815680The Fluke 115 Reviewhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg818828/#msg818828My old Mastech MS9508 / Cen-tech P37772https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg829927/#msg829927Discussing input protection circuitshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg832724/#msg832724The SONY Cyber-shot DSC-RX10M2 high speed Sony camerahttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg841421/#msg841421The UNI-T UT15C VoltStickhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg848706/#msg848706The Keysight U1231Ahttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg852693/#msg852693First look at the current inputshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg863105/#msg863105The VICI VC99https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg881819/#msg881819The HIOKI DT4252https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg890263/#msg890263The UNI-T UT181Ahttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg908123/#msg908123Talking about ESDhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg911717/#msg911717The UNI-T UT181A Repairshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg915451/#msg915451Low cost pocket metershttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg934733/#msg934733Testing various DMM probeshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg945681/#msg945681The TPI 194 IIhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg967246/#msg967246Temperature testing Part Ihttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg985119/#msg985119Modifying the UNI-T UT61E (added robustness, backlight)https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1023221/#msg1023221YX-360 analog meterhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1025998/#msg1025998The Brymen BM235https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1030093/#msg1030093Pen Metershttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1054346/#msg1054346Modifying the UNI-T UT61E (Improving temperature drift)https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1074263/#msg1074263The CEM DT-9939 / Extech EX540https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1110590/#msg1110590Designing an ESD gunhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1126104/#msg1126104The Woods DMMW3 pocket meterhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1146838/#msg1146838The ANENG metershttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1149808/#msg1149808Testing various DMM high current shuntshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1159237/#msg1159237Modifying the UNI-T UT61E (20A measurements)https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1168820/#msg1168820Modifying the UNI-T UT61E (Low Burden Voltage)https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1182031/#msg1182031SIBA branded UXCELL Multimeter Fuse, Real or Counterfeithttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1196539/#msg1196539The Gossen Metrawatt Metrahit Ultra M248Bhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1207306/#msg1207306The Gossen goes to the chamber along with some lower cost metershttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1209697/#msg1209697Dave sends a 121GW prototypehttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1231731/#msg1231731Testing Dave's ASTM fuseshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1236035/#msg1236035Mr Jouleshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1245107/#msg1245107My first Fluke 189, Finally a Fluke meter that I would actually usehttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1258001/#msg1258001PlastX, restoring lenshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1262271/#msg1262271Dave runs a crude HV testhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1282305/#msg1282305The ANENG 8008https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1284726/#msg1284726Transient Testing Resistorshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1295646/#msg1295646ANENG, 14KV or Busthttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1299489/#msg1299489Selector Switch Life Cycle Testing Part Ihttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1313951/#msg1313951The ALL-SUN EM135 Automotive Meterhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1337607/#msg1337607Selector Switch Life Cycle Testing Part IIhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1345200/#msg1345200Harbor Freight's CEN-TECH 95670, the rebranded E0SUN EM129 automotive meterhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1369480/#msg1369480Upgrades to my temperature chamber made from a meat packing boxhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1371562/#msg1371562The Brymen BM319s Automotive Meterhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1382595/#msg1382595The Brymen BM869s 50,000 Cycle Switch Life Testhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1386207/#msg1386207Repeating the Brymen BM869s Transient Testhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1400700/#msg1400700The Brymen BM839 Professional Meterhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1405549/#msg1405549The Brymen BM869s, It's 14KV or Busthttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1407796/#msg1407796Repairing the homemade wideband high voltage probehttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1417243/#msg1417243The Fluke 87V, hot off the production line, full on testinghttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1429536/#msg1429536The Fluke 87V, Extended High Voltage Testinghttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1460870/#msg1460870The Fluke 87V, Another look at the old 87V and why it failedhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1467255/#msg1467255The Fluke T6-600, a responce to AvEhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1519018/#msg1519018Appling 1KV to various meter's, a responce to VoltLoghttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1547579/#msg1547579Member Kean's Damaged 121GW, trying to determine the root causehttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1598113/#msg1598113Lighting strikes and damages some of my test equipmenthttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1646627/#msg1646627The MeterK MK01https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1684985/#msg1684985Transient Testing a Vintage Fluke 189https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1748807/#msg1748807The Brymen BM27s / Amprobe PM55A, is it really as bad as member True claims?https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1787117/#msg1787117Applying 1KVDC to various 4.7M resistors, preparing for a possible future testhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1787645/#msg1787645Viewer questions and commentshttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1822403/#msg1822403The Brymen BM869s is directly exposed to several Watts of 7MHz CWhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1906376/#msg1906376The Brymen BM27s / Amprobe PM55A, Round I of testinghttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1908218/#msg1908218Demonstrating using Labview to communicate w/ 121GW and UT181A over BlueToothVaseline? Yes, that's right. Future Darwin Awardhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg1929244/#msg1929244The Owon B41T+ reviewhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg2053840/#msg2053840Measuring battery lifehttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg2081572/#msg2081572Rebuilding my first digital volt meter, the Fluke 8000Ahttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg2174864/#msg2174864The Yokogawa TY720 reviewhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg2223951/#msg2223951Vibration Testinghttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg2299404/#msg2299404The Brymen BM27s pocket meter, Round II low battery, cold Winter months and vibrationhttps://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg2344941/#msg2344941

author: N2IXK
author_rank: Frequent Contributor
timestamp: June 06, 2015, 01:09:35 am
content: Any muiltimeter with a legitimate Cat III rating can handle Cat II circuits.The higher the Category rating, the higher energy the meter is safe with. You can always use a Cat III or Cat IV meter on lower rated circuits, but not the other way around....

author: joeqsmith
author_rank: Super Contributor
timestamp: June 06, 2015, 01:14:38 am
content: After doing many searches on this site, I see a lot of posts about how meters are rated and tested. There were even a few posts where people attempted to put some high voltage on them. To be clear, my plan is not to do an insulation test. I am interested in surge. My plan is to construct a small generator that I will use to weed out the worst meters. If any meters are working after my basic test, I plan to further test them to the actual standards.CAT III 600 would require the surge use a 2 ohm source with a 6KV peak (3000 Amps peak). This would ride on top of the AC. Nasty stuff. CAT II uses a 4KV peak with a 12 ohm source (333 Amps peak). The test is the standard 8/20 waveform with a short applied or 1/50 with an open.A few good articles if you are interested:http://www.grainger.com/content/safety-digital-multimeterhttp://cp.literature.agilent.com/litweb/pdf/5990-4578EN.pdfhttp://faculty.riohondo.edu/jfrala/fluke_multimeters_-_abcs_of_multimeter_safety_multimeter_safety_and_you_application_note.pdf

author: joeqsmith
author_rank: Super Contributor
timestamp: June 06, 2015, 01:49:15 am
content: To start out, I need a generator that can create something close to the CAT II waveform. You saw from my first post my quick generator. This thing could hardly do much of anything.Over the last few days I built up several circuits, blew up every bench supply I have (an repaired them) and am close now to what I am looking for.My plan to do a sort of hybrid waveform. I plan to limit the peak to 2KV but stay with the 2 ohm source. I also plan to limit the duration of the pulse (not sub 1.0us like my first throw together setup). I plan to cut it in half. For a CAT III meter this will be no problem what so ever as it is 1/3 the peak and half the duration with the same impedance.The second generator I cobbled up worked fairly well with a 12 ohm source but I wanted something that could do the above and put out that full 1000 Amps.The DOE Handbook Electrical Safety is available on-line. I have played with KV low current equipment most of my life from TV and radios to modern test equipment. So I am not concerned about this little project. However, I thought it would be interesting to highlight a few paragraphs from this document.To create the waveform, I have been using a 500mA wall mount supply. I use this to create a high voltage signal that is rectified and stored into a bank of capacitors.In Fig. 3-4. Complete electrical hazard classification system showing 5 major groups and 54 classes. You can see capacitors are called out as Classes 3.x. They are broken down by operating voltage.13.7.3.3 Safety PracticesAn analysis of high-voltage circuits should be performed by a qualified person before workbegins unless all exposed energized parts are guarded as required for high-voltage work. Theanalysis must include fault conditions where circuit current could rise above the nominal ratedvalue. Depending on the results of the analysis, any of the following may apply:1. If the analysis concludes that the current is above 5 mA or stored high-voltage capacitiveenergy is above 1 joule for voltages between 100 and 400 V DC, or above 0.25 joule forvoltages equal to or greater than 400 V, then the work is considered to be energized workand should be performed in accordance with Chapter 2, "General Requirements" and/orChapter 3, "Hazard Analysis." See Chapter 3 for details on electrical hazard classification.2. If the analysis concludes that the current is between 0.5 mA and 5 mA and between 0.25and 1 joules, then the worker may be exposed to a secondary hazard (e.g., startle reaction)that must be mitigated.3. If the analysis concludes that the current is below 0.5 mA and below 0.25 joules, then theworker exposure is minimal and no special precautions are required, even for high voltagecircuits.From above, I plan to run the storage caps at 2KV. Well above the 400V limit. Looking at Fig. 3-9. Hazard Classes 3.x, capacitors, > 400 V, we can see that for 1-10 Joules, it is considered Class 3.3d. This is a Red colored box.10) A red Class (X.3) indicates injury or death could occur by proximity or contact; oftenthe hazard is shock, contact burn, or arc-flash burn; engineering controls arenecessary for operation (e.g., listing or equipment approval), and administrativecontrols are necessary for electrical work in this Class.It should be obvious what the above means....

author: joeqsmith
author_rank: Super Contributor
timestamp: June 06, 2015, 01:53:39 am
content: After making some calculations for the controller and output stages I ran a quick simulation of both. Attached you can see the simulated response with a 1Meg and a 0.1 ohm load attached. Not quite a 1000 Amps in the simulation.

author: joeqsmith
author_rank: Super Contributor
timestamp: June 06, 2015, 03:38:02 am
content: Here is the final test generator. No high voltage is exposed except at the banana connectors that plug into the target. I was going to run it from batteries and still may. There are two banana jacks on the side used to supply the power. The key is plastic and is used to disable the unit. The cable is silicone and the connectors are a CSCB series, both rated for much higher voltages than I plan to run.In the picture, you can see the damaged BK meter with the Pearson current transformer. This is a 5000A 20MHz part, PN 410.Looking through Amazon, there is not a great way to search for CAT ratings. Interesting is that all the work that was put into the DVM spreadsheet and all the concern for safety, I can't seem to find them rated by CAT an fuses. I read through the forum about meters that don't meet their specs.

author: Halvmand
author_rank: Regular Contributor
timestamp: June 06, 2015, 11:03:48 am
content: Interesting. Looking foward to se some test results.Do you have any meters in mind for destruction?I would personally like to see the fluke ripoff get exited.http://www.ebay.com/itm/F14129-Aimometer-MS8215-Auto-Range-Digital-Multimeter-DMM-AC-DC-Voltmeter-Amme-/261831441592?pt=LH_DefaultDomain_0&hash=item3cf65ebcb8

author: Halvmand
author_rank: Regular Contributor
timestamp: June 06, 2015, 11:08:18 am
content: Oops. That is only CAT II rated.

author: Fungus
author_rank: Super Contributor
timestamp: June 06, 2015, 12:50:35 pm
content: Quote from: joeqsmith on June 06, 2015, 12:54:30 amAnything that's CAT III is also CAT II.Quote from: joeqsmith on June 06, 2015, 12:54:30 amThe difference between CAT II and CAT III is very subtle in practice.You can't tell if a mains socket is CAT II or CAT III just by looking at it. It's mostly to do with the distance from the circuit breakers (ie. the length/inductance of the wire between you and the distribution panel).Quote from: joeqsmith on June 06, 2015, 12:54:30 amMe? I wouldn't use anything less than CAT III for regular mains work and I'd want a meter which IKNOWis CAT III, which in practice means Fluke. The numbers printed on the front of certain other brands of meter have been shown to be liesmanytimes in these forums.A Fluke 101 can be had for under $45, is easy to find, and comes with proper covered probes for mains AC work.For that price I don't see any point in using anything else.

author: G0HZU
author_rank: Super Contributor
timestamp: June 06, 2015, 01:20:46 pm
content: QuoteThe only thing I'd add to that is that for the vast majority of today's hobbyists, one should rarely need to directly measure the mains voltage with a meter anyway.I avoid it as much as possible and use a sealed 'meter in a plug' if I'm curious about what the mains voltage is. Otherwise, I'd rather debug any mains wiring inside a piece of electronics gear with the unit switched off and unplugged from the mains and after a discharge.To put this in perspective, I don't think I've measured the mains voltage directly with a DMM for many years. Obviously it would be different if I was an electrical engineer working on domestic or commercial power distribution etc but I'm quite happy to use basic DMMs (here and at work) for most low voltage electronics work. But I always keep them well away from mains voltage (230V AC here in the UK).

author: joeqsmith
author_rank: Super Contributor
timestamp: June 06, 2015, 03:47:20 pm
content: Quote from: Halvmand on June 06, 2015, 11:03:48 amYes, I have started to make a list.Mastech MS8264, 8261, 8217 and 2008B. The Extech MN15A. The UNI-T UT90A.I don't care if it had a bad review, was shown to have a glass fuse or appeared to have no protection at all. I don't care what color it is, how many features it has or how many digits. I am looking for anything under $50 with a CAT III 600V rating and fused current or clamp. I am not affiliated with any company and have no bias towards any manufacture of hand held meters. So any meter that meets the above, I would add to the list.Quote from: Fungus on June 06, 2015, 12:50:35 pmI'll check. I have another Fluke in mind and am not apposed to testing more of them if they meet the criteria.Currently I am working on a short video showing how the generator works and the waveforms it produces. I was looking around the room for loads, and there was an LED bulb that would no longer turn on. I connected the bulb to the generator and zapped it. You know, that thing came back to life! I kid you not! I screwed it back into my fixture and it is still on. Maybe a lead free solder joint failure.......

author: Fungus
author_rank: Super Contributor
timestamp: June 06, 2015, 04:23:46 pm
content: Quote from: joeqsmith on June 06, 2015, 03:47:20 pmUnder $42.50 delivered to your door:http://www.ebay.com/sch/i.html?_nkw=fluke+101

author: joeqsmith
author_rank: Super Contributor
timestamp: June 06, 2015, 05:44:16 pm
content: I closed my Ebay's account many years ago but I did find it on Amazon for under $50, ships direct from China with free shipping.As I plan to buy one higher cost DVM, I started to look at the warranty and manuals. Let's look at the 101 manual.QuoteWould a manufacture consider purposely testing their products, misuse or abnormal? I guess we will find out.For the first tests I plan to use my homemade surge generator to test all of the meters. One thing that may not be clear is for my basic home surge tests, I am not going to inject on top of the input signal. Surge would normally ride on the AC and would be tested +/- at 0, 90, 180 270. It should be clear what this means as far as the peak voltages. My concern is not so much the peak, but the energy available from the line after an arc. When I made this video showing the effects of having the surge on top of a 24V DC source it's not hard to understand why.https://www.youtube.com/watch?feature=player_detailpage&v=ZeRkEKBYdzw#t=64

author: joeqsmith
author_rank: Super Contributor
timestamp: June 07, 2015, 01:18:07 am
content: Here's the first of what will be several videos showing the my homemade scaled down surge generator in operation. You can see the output waveform with various loads attached.

author: Halvmand
author_rank: Regular Contributor
timestamp: June 07, 2015, 06:30:07 pm
content: Great video.I think this one from amprobe could be a fun test:Amprobe AM-510 for 44 $ on ebayhttp://www.ebay.com/itm/Amprobe-AM-510-Commercial-Residential-Multimeter-with-Non-Contact-Voltage-New-/351412552068?pt=LH_DefaultDomain_0&hash=item51d1d20184This too:Amprobe AM-34 for 45 $www.ebay.com/itm/Amprobe-AM-34-Cat-III-AUTO-Digital-Multimeter-/271867163408?pt=LH_DefaultDomain_0&hash=item3f4c8bb310Or this one if it would drop just a tinsy bit in price and be available outside europe. From your video you don't sound european.PeakTech 2015. It has really good features i think. Could not find a teardown of it, but some of the higher end models seems well build.http://www.peaktech.de/productdetail/kategorie/multimeter/produkt/p-2015.html

author: blackbird
author_rank: Regular Contributor
timestamp: June 07, 2015, 07:36:15 pm
content: I would like to see the Elix AL72D tested. It is a cheap multimeter sold by ALDI and some other discount supermarkets. They claim CATII and maybe it will survive the 750VAC or 1KVDC.This model is also sold as the Range RE93A and I think under many other 'brands'.The retailprice of this multimeter is somewhere between €10 and €15.

author: MarkL
author_rank: Unknown
timestamp: June 07, 2015, 09:18:38 pm
content: joeqsmith:I'm interested in your surge generator. Perhaps a schematic would be helpful.How are you triggering the discharge of the capacitor bank? Or are you just charging it until it arcs over in the DUT?

author: joeqsmith
author_rank: Super Contributor
timestamp: June 07, 2015, 09:25:15 pm
content: Quote from: Halvmand on June 07, 2015, 06:30:07 pmThanks. Glad you enjoyed the sparks.I like that 510. I looked for the PeakTech but it does not appear available. I assume there are many more that fall into this price/rating range.Quote from: blackbird on June 07, 2015, 07:36:15 pmI looked for this meter and could not find it. However, I am really looking for CAT III 600 and up.I have now added some test lead points and a ground clip.

author: joeqsmith
author_rank: Super Contributor
timestamp: June 08, 2015, 02:46:36 am
content: You saw the sparks fly from my old BK that was CAT II rated. Then you saw the sparks fly from my old Fluke.Against my better judgement, I decided to sacrifice one more meter to the surge god. After seeing how bad the Fluke arced and blowing the control IC off the BK, I thought it would be good to tape it. The DM-301 appears as cheap as they come. It has no CAT rating at all. There are no CE or TUV marks. There is no brand name on it but it was made in Korea. I picked it up in a Sears outlet just to have a handheld. It got used a lot and is in pretty rough shape now. The LCD is cracked and I no longer use it so putting it on my scaled down surge generator is no problem.In this video I talk a little about how I plan to go about evaluating the low cost meters. I also talk a little about the 1010 standard and how I base my pass/fail criteria on it.When you start looking at 5 seconds between transients, 5 transients per mode, say 3 connectors testing all combinations, say 10 modes, and both positive and negative.... Well that's a very very long time to test each meter. This can make for a VERY boring video. If you ever had to test a product to these standards, you know what I mean. It's a lot of waiting.As you watch this video, I stripped out most of the dead time waiting for the tests. I also did not show every dial setting being tested. I did leave some of it in order to show how slow this testing can go. So if you get bored watching, just fast forward.If you are looking for a video where 1K resistors are measured and I talk about how big the fuses are, how soft the rubber case is or how the plastic feels or the colors of the plastic, these videos will not be for you. But if you want to see some low cost meters getting hit with the surge, get some popcorn. I plan to increase the energy to each and every one of them to destruction. Only one meter will come out on top and I don't care which brand or where it was made.Once I have found the best of the low cost meters that I have purchased, then next question I need to answer is can a higher priced name brand meter go up against it.Without further adieu, setting the bar low as it gets, here's the no brand name DM 301. Enjoyhttps://www.youtube.com/watch?v=pInd17ibzDg&feature=youtu.be

author: joeqsmith
author_rank: Super Contributor
timestamp: June 09, 2015, 01:26:49 am
content: Tonight I increased the voltage from my homemade surge generator until the unbranded DM-301 failed. This will be the starting point for testing the new meters. If the new CAT III 600 rated meters I order can't out perform this super low cost unrated meter, well, those would be some very poor meters. The bar is set low.Short clip showing the breakdown.https://www.youtube.com/watch?v=USwqyjUD-jw&feature=youtu.be

author: ivan747
author_rank: Super Contributor
timestamp: June 09, 2015, 02:47:24 am
content: May I suggest the Amprobe AM220? It has what would appear to be HRC fuses but are really normal fuses with a ceramic tube, no sand and potentially no vacuum.

author: joeqsmith
author_rank: Super Contributor
timestamp: June 11, 2015, 01:27:32 am
content: I have narrowed my search for a higher end meter test against what ever low cost meter survives to the highest energy surge. Keysight's U1272A, Fluke's 28II or the 87V. All are in roughly the same price range. Leaning towards the Keysight only because I have not had any failures with my HP meters and you saw what happened with my first Fluke.If anyone out there has actually ran surge tests on these and have an idea where they fail, it would be helpful. I would rather have the more robust meter of the three for my testing.

author: ivan747
author_rank: Super Contributor
timestamp: June 11, 2015, 03:30:25 am
content: Dave hates (feline) cats. If you rename the thread he might see it.

author: Mark
author_rank: Frequent Contributor
timestamp: June 11, 2015, 09:43:20 am
content: Quote from: MarkL on June 07, 2015, 09:18:38 pmI am also interested in this as I am working on surge testing at the moment, it would be interesting to compare home made vs professional unit. Can you post your schematic JoeQ?

author: joeqsmith
author_rank: Super Contributor
timestamp: June 11, 2015, 11:00:39 am
content: The BK 2703C, Mastech MS8264, Amprobe AM-510, Extech MN16A, Fluke 101 are now on order. Does the Fluke 101 come out on top? Do they all outperform my unbranded DM-301?Quote from: Mark on June 11, 2015, 09:43:20 amWhile I mentioned it in Part 2, for any questions about surge generators refer to the IEC 61180-1.