On Monday, January 9, 2023 at 5:47:17 AM UTC+11, Flyguy wrote:> On Sunday, January 8, 2023 at 6:41:15 AM UTC-8, bill....@ieee.org wrote: > > On Sunday, January 8, 2023 at 5:52:35 PM UTC+11, Flyguy wrote: > > > On Saturday, January 7, 2023 at 11:31:33 AM UTC-8, Ed Lee wrote: > > > > On Saturday, January 7, 2023 at 11:22:49 AM UTC-8, Fred Bloggs wrote: > > > > > On Saturday, January 7, 2023 at 2:16:50 PM UTC-5, Ed Lee wrote: > > > > > > On Saturday, January 7, 2023 at 11:10:02 AM UTC-8, Fred Bloggs wrote: > > > > > > > On Saturday, January 7, 2023 at 1:42:05 PM UTC-5, Ed Lee wrote: > > > > > > > > On Saturday, January 7, 2023 at 10:14:06 AM UTC-8, John Larkin wrote: > > > > > > > > > On Sat, 7 Jan 2023 09:34:02 -0800 (PST), Fred Bloggs <bloggs.fred...@gmail.com> wrote: > > > > > > > > > > > > > > > > > > >On Saturday, December 31, 2022 at 1:19:58 PM UTC-5, Ed Lee wrote: > > <snip> > > > If you are going to be working on HV circuits (>240 V) ONLY use DMMs with a CAT certification (which cheap Chinese meters don't have). > > > https://www.fluke.com/en-us/learn/blog/safety/multimeter-guide > > Which doesn't tell you much. > > It tells you everything you need to know to make a purchasing decision. This IS NOT a designer's guide, Bozo.This is sci.electronics.,design. The people who post here do imagine that they design electronics, even clowns like you. The link you posted wasn't informative at the level you'd need if you wanted to make an informed decision about buying a multimeter, not that you;d know anything about that> > "The latest UL standard for electrical test instruments is UL 61010B-1, which is a revision of 3111-1. It specifies the general safety requirements, such as material, design, and testing requirements, and the environmental conditions in which the standard applies. UL 3111-2-031 lists additional requirements for test probes. The requirements for hand-held current clamps, such as the current measuring portion of clamp meters, are included in UL 3111-2-032. > > > > UL standards are gradually being harmonized with similar international standards, such as those published by IEC. Until this is completed, there may be significant differences between each group's standards. For example, IEC 61010-1 2nd Edition includes requirements for voltage-measuring instruments in CAT IV environments. UL 61010B-1 doesn't." > > > > What Flyguy might be saying - if he knew what he was talking out - is that there are safety standards for multimeters. In the US they are published by the Underwriter > > Laboratory. > > I am WELL AWARE of UL and other testing labs.But not aware enough top pull out an actual standard that said anything specific.> > There are also international safety standards. > > > > https://www.nema.org/standards/international/the-iec-and-nema > > > > The International Electrotechnical Commission (IEC) headquartered in Geneva, Switzerland is the top level body. > > > > A chinese multi-meter might well not conform to an American Underwriters Laboratory standard, but will probably conform to the relevant IEC standard, which isn't going to be much different. > > Pure SPECULATION by Bozo completely UNVERIFIED by ANY facts whatsoever. But, why am I not surprised coming from Bill?Sewage Sweeper didn't produce any facts of his own - and never does. When he's exposed to them, he ignores them, but he'd great at recycling the abuse he gets, even when it is totally irrelevant.> > A cheap chinese meter might be truly cheap and nasty, and correspondingly dangerous, but anybody who sold it to you would risk being sued if it was.> LOL! Just TRY suing a Chinese company - just TRY!!You don't sue the manufacturer. You sue the retailer who sold you a device that wasn't fit for the purpose for which it was advertised.> > It's more likely to be cheap because it was produced in high volume, rather than because the manufacturer cut any corners. I've ran into one American instrument that didn't meet their published specifications, which is a slightly different kind of problem - it wasn't certainly wasn't cheap.> No, Bozo, they cut ALL KINDS of corners: https://www.youtube.com/watch?v=iGUiZT6kLDkA youtube video is evidence?> Notice that this meter has NO certification marks. And for GOOD REASON: it would NEVER pass.Why should I care what some cheapskate idiot bought on E-bay? The device was CE marked, but the camera didn't linger longer to pick up the number of the relevant standard. -- Bill Sloman, Sydney
HV damages meter?
Started by ●December 31, 2022
Reply by ●January 8, 20232023-01-08
Reply by ●January 8, 20232023-01-08
On Monday, January 9, 2023 at 8:33:12 AM UTC+11, Jeroen Belleman wrote:> On 2023-01-08 20:44, John Larkin wrote: > > On Sun, 8 Jan 2023 19:02:15 -0000 (UTC), anti...@math.uni.wroc.pl > > wrote: > > > >> John Larkin <jla...@highlandsnipmetechnology.com> wrote: > >>> On Sat, 7 Jan 2023 01:04:32 -0000 (UTC), anti...@math.uni.wroc.pl > >>> wrote: > >>> > >>>> Ed Lee <edward....@gmail.com> wrote: > >>>>> But not immediately. I tested 400V occasionally, but couple of them died while testing 12V. I am wondering it 400V weaken the meter. > >>>> > >>>> High voltage can destroy resistors, but this seem to be quite fast. > >>>> > >>>>> The old CenTech meters are 1000V, but the new models are 250V. Why even bother to have 50V more than the next range of 200V. Perhaps it's just same design with new label, when they got enough reports/complaints. > >>>> > >>>> Lot of folks live in countries where line voltage is 230V. So 50 volts > >>>> makes a lot of difference. > >>>> > >>>>> I am wondering if it's worth picking up some of the older 1000V models off ebay. > >>>> > >>>> I know nothing about CenTech meters. But I have several "DT830B" > >>>> meters. Available schematics shows 3 resistors in series for 1000V. > >>>> My oldest one have 2 resistors. Newest one have single resistor. > >>>> Standard miniature resistors are rated for 250V, one can get > >>>> better ones, but I doubt that one can get cheaply 1000V capable > >>>> ones. Still, meter is marked as 1000V DC, 700V AC (the same > >>>> as old meters). > >>> > >>> They eliminated 0.2 cents worth of resistors. Ignore temperature and > >>> voltage coefficient effects. Maybe some of that is mathed out?Or they bought a better resistor. Until you take it off the board and look at its construction with fairly high tech gear you cant tell what they have done.> >>> Chinese product prices ratchet towards cheap, and the specs ratchet > >>> deep into the lies region. Chinese amps and volts and per cent are > >>> about 10:1 off from SI standards. > >> > >> Well, the cheap "DT830B" were surprisingly accurate. I have > >> used 4 to measure the same voltage. IIRC the differences > >> were in last digit and did not exceed 2 counts. They were > >> bought from different sources at different times, so it > >> is unlikly to be the same error on all. And they agreed > >> with better meter. Newest ones seem to have larger > >> errors, but still well withing specs. > >> > >> AFAICS biggest problem with cheap meters are test leads, > >> they tend to fail rather quickly. Second problem is > >> main switch, which is formed from part of PCB. It > >> seem to degrade with use. And failing switch can > >> produce all kinds of wrong results. > > > > Why buy cheap junk test equipment? > > > > Why buy cheap junk anything? > > > Because cheap isn't always junk and junk isn't always cheap? > Sometimes it's kind of hard to tell.If the cheap equipment conforms to the relevant standards - which nobody posting here has identified - it shouldn't be junk. Sewage Sweeper wittered on about CAT certification, but didn't provide a link to the relevant American underwriter's Laboratory specification. I pointed out that the Underwriters Laboratory are working to align their nationnal specifications with the International Electrotechnical Commission (IEC) specifcations, which Chinese manufacturers aiming at internatioal markets might go for. Sewage Sweeper naturally ignored this point, probably because he didn't understand it. -- Bill Sloman, Sydney
Reply by ●January 10, 20232023-01-10
On Sunday, January 8, 2023 at 7:50:20 PM UTC-8, bill....@ieee.org wrote:> On Monday, January 9, 2023 at 5:47:17 AM UTC+11, Flyguy wrote: > > On Sunday, January 8, 2023 at 6:41:15 AM UTC-8, bill....@ieee.org wrote: > > > On Sunday, January 8, 2023 at 5:52:35 PM UTC+11, Flyguy wrote: > > > > On Saturday, January 7, 2023 at 11:31:33 AM UTC-8, Ed Lee wrote: > > > > > On Saturday, January 7, 2023 at 11:22:49 AM UTC-8, Fred Bloggs wrote: > > > > > > On Saturday, January 7, 2023 at 2:16:50 PM UTC-5, Ed Lee wrote: > > > > > > > On Saturday, January 7, 2023 at 11:10:02 AM UTC-8, Fred Bloggs wrote: > > > > > > > > On Saturday, January 7, 2023 at 1:42:05 PM UTC-5, Ed Lee wrote: > > > > > > > > > On Saturday, January 7, 2023 at 10:14:06 AM UTC-8, John Larkin wrote: > > > > > > > > > > On Sat, 7 Jan 2023 09:34:02 -0800 (PST), Fred Bloggs <bloggs.fred...@gmail.com> wrote: > > > > > > > > > > > > > > > > > > > > >On Saturday, December 31, 2022 at 1:19:58 PM UTC-5, Ed Lee wrote: > > > <snip> > > > > If you are going to be working on HV circuits (>240 V) ONLY use DMMs with a CAT certification (which cheap Chinese meters don't have). > > > > https://www.fluke.com/en-us/learn/blog/safety/multimeter-guide > > > Which doesn't tell you much. > > > > It tells you everything you need to know to make a purchasing decision. This IS NOT a designer's guide, Bozo. > This is sci.electronics.,design. The people who post here do imagine that they design electronics, even clowns like you. > The link you posted wasn't informative at the level you'd need if you wanted to make an informed decision about buying a multimeter, not that you;d know anything about that > > > "The latest UL standard for electrical test instruments is UL 61010B-1, which is a revision of 3111-1. It specifies the general safety requirements, such as material, design, and testing requirements, and the environmental conditions in which the standard applies. UL 3111-2-031 lists additional requirements for test probes. The requirements for hand-held current clamps, such as the current measuring portion of clamp meters, are included in UL 3111-2-032. > > > > > > UL standards are gradually being harmonized with similar international standards, such as those published by IEC. Until this is completed, there may be significant differences between each group's standards. For example, IEC 61010-1 2nd Edition includes requirements for voltage-measuring instruments in CAT IV environments. UL 61010B-1 doesn't." > > > > > > What Flyguy might be saying - if he knew what he was talking out - is that there are safety standards for multimeters. In the US they are published by the Underwriter > > > Laboratory. > > > > I am WELL AWARE of UL and other testing labs. > But not aware enough top pull out an actual standard that said anything specific. > > > There are also international safety standards. > > > > > > https://www.nema.org/standards/international/the-iec-and-nema > > > > > > The International Electrotechnical Commission (IEC) headquartered in Geneva, Switzerland is the top level body. > > > > > > A chinese multi-meter might well not conform to an American Underwriters Laboratory standard, but will probably conform to the relevant IEC standard, which isn't going to be much different. > > > > Pure SPECULATION by Bozo completely UNVERIFIED by ANY facts whatsoever. But, why am I not surprised coming from Bill? > > Sewage Sweeper didn't produce any facts of his own - and never does. When he's exposed to them, he ignores them, but he'd great at recycling the abuse he gets, even when it is totally irrelevant.No Bozo, it is YOU that doesn't ever produce any facts. You DO produce a bunch of lame excuses why you CAN'T produce the facts, though.> > > > A cheap chinese meter might be truly cheap and nasty, and correspondingly dangerous, but anybody who sold it to you would risk being sued if it was. > > LOL! Just TRY suing a Chinese company - just TRY!! > You don't sue the manufacturer. You sue the retailer who sold you a device that wasn't fit for the purpose for which it was advertised.Hey Bozo, look where these meters come from: straight from China.> > > It's more likely to be cheap because it was produced in high volume, rather than because the manufacturer cut any corners. I've ran into one American instrument that didn't meet their published specifications, which is a slightly different kind of problem - it wasn't certainly wasn't cheap. > > > No, Bozo, they cut ALL KINDS of corners: https://www.youtube.com/watch?v=iGUiZT6kLDk > A youtube video is evidence?Fucking YES!> > Notice that this meter has NO certification marks. And for GOOD REASON: it would NEVER pass. > Why should I care what some cheapskate idiot bought on E-bay? The device was CE marked, but the camera didn't linger longer to pick up the number of the relevant standard.WHY are you posting this bullshit, then? You obviously DO care!> > -- > Bozo Bill Sloman, SydneyBozo's Sewage Sweeper
Reply by ●January 10, 20232023-01-10
On Sunday, January 8, 2023 at 7:50:43 PM UTC-8, bill....@ieee.org wrote:> On Monday, January 9, 2023 at 8:33:12 AM UTC+11, Jeroen Belleman wrote: > > On 2023-01-08 20:44, John Larkin wrote: > > > On Sun, 8 Jan 2023 19:02:15 -0000 (UTC), anti...@math.uni.wroc.pl > > > wrote: > > > > > >> John Larkin <jla...@highlandsnipmetechnology.com> wrote: > > >>> On Sat, 7 Jan 2023 01:04:32 -0000 (UTC), anti...@math.uni.wroc.pl > > >>> wrote: > > >>> > > >>>> Ed Lee <edward....@gmail.com> wrote: > > >>>>> But not immediately. I tested 400V occasionally, but couple of them died while testing 12V. I am wondering it 400V weaken the meter. > > >>>> > > >>>> High voltage can destroy resistors, but this seem to be quite fast. > > >>>> > > >>>>> The old CenTech meters are 1000V, but the new models are 250V. Why even bother to have 50V more than the next range of 200V. Perhaps it's just same design with new label, when they got enough reports/complaints. > > >>>> > > >>>> Lot of folks live in countries where line voltage is 230V. So 50 volts > > >>>> makes a lot of difference. > > >>>> > > >>>>> I am wondering if it's worth picking up some of the older 1000V models off ebay. > > >>>> > > >>>> I know nothing about CenTech meters. But I have several "DT830B" > > >>>> meters. Available schematics shows 3 resistors in series for 1000V. > > >>>> My oldest one have 2 resistors. Newest one have single resistor. > > >>>> Standard miniature resistors are rated for 250V, one can get > > >>>> better ones, but I doubt that one can get cheaply 1000V capable > > >>>> ones. Still, meter is marked as 1000V DC, 700V AC (the same > > >>>> as old meters). > > >>> > > >>> They eliminated 0.2 cents worth of resistors. Ignore temperature and > > >>> voltage coefficient effects. Maybe some of that is mathed out? > Or they bought a better resistor. Until you take it off the board and look at its construction with fairly high tech gear you cant tell what they have done. > > >>> Chinese product prices ratchet towards cheap, and the specs ratchet > > >>> deep into the lies region. Chinese amps and volts and per cent are > > >>> about 10:1 off from SI standards. > > >> > > >> Well, the cheap "DT830B" were surprisingly accurate. I have > > >> used 4 to measure the same voltage. IIRC the differences > > >> were in last digit and did not exceed 2 counts. They were > > >> bought from different sources at different times, so it > > >> is unlikly to be the same error on all. And they agreed > > >> with better meter. Newest ones seem to have larger > > >> errors, but still well withing specs. > > >> > > >> AFAICS biggest problem with cheap meters are test leads, > > >> they tend to fail rather quickly. Second problem is > > >> main switch, which is formed from part of PCB. It > > >> seem to degrade with use. And failing switch can > > >> produce all kinds of wrong results. > > > > > > Why buy cheap junk test equipment? > > > > > > Why buy cheap junk anything? > > > > > Because cheap isn't always junk and junk isn't always cheap? > > Sometimes it's kind of hard to tell. > If the cheap equipment conforms to the relevant standards - which nobody posting here has identified - it shouldn't be junk. > > Sewage Sweeper wittered on about CAT certification, but didn't provide a link to the relevant American underwriter's Laboratory specification. > > I pointed out that the Underwriters Laboratory are working to align their nationnal specifications with the International Electrotechnical Commission (IEC) specifcations, which Chinese manufacturers aiming at internatioal markets might go for.The CAT ratings come FROM the IEC, Bozo: https://www.digikey.com/en/blog/what-are-multimeter-cat-safety-ratings So UL is just certifying that the meter conforms to this specification. BTW, your spelling is getting WORSE, with THREE blunders in ONE sentence.> > Sewage Sweeper naturally ignored this point, probably because he didn't understand it.No, YOU ignored the provenance.> > -- > Bozo Bill Sloman, SydneyBozo's Sewage Sweeper
Reply by ●January 10, 20232023-01-10
On Tuesday, January 10, 2023 at 3:11:41 PM UTC+11, Flyguy wrote:> On Sunday, January 8, 2023 at 7:50:20 PM UTC-8, bill....@ieee.org wrote: > > On Monday, January 9, 2023 at 5:47:17 AM UTC+11, Flyguy wrote: > > > On Sunday, January 8, 2023 at 6:41:15 AM UTC-8, bill....@ieee.org wrote: > > > > On Sunday, January 8, 2023 at 5:52:35 PM UTC+11, Flyguy wrote: > > > > > On Saturday, January 7, 2023 at 11:31:33 AM UTC-8, Ed Lee wrote: > > > > > > On Saturday, January 7, 2023 at 11:22:49 AM UTC-8, Fred Bloggs wrote: > > > > > > > On Saturday, January 7, 2023 at 2:16:50 PM UTC-5, Ed Lee wrote: > > > > > > > > On Saturday, January 7, 2023 at 11:10:02 AM UTC-8, Fred Bloggs wrote: > > > > > > > > > On Saturday, January 7, 2023 at 1:42:05 PM UTC-5, Ed Lee wrote: > > > > > > > > > > On Saturday, January 7, 2023 at 10:14:06 AM UTC-8, John Larkin wrote: > > > > > > > > > > > On Sat, 7 Jan 2023 09:34:02 -0800 (PST), Fred Bloggs <bloggs.fred...@gmail.com> wrote: > > > > > > > > > > > > > > > > > > > > > > >On Saturday, December 31, 2022 at 1:19:58 PM UTC-5, Ed Lee wrote: > > > > <snip> > > > > > If you are going to be working on HV circuits (>240 V) ONLY use DMMs with a CAT certification (which cheap Chinese meters don't have). > > > > > https://www.fluke.com/en-us/learn/blog/safety/multimeter-guide > > > > > > > > Which doesn't tell you much. > > > > > > It tells you everything you need to know to make a purchasing decision. This IS NOT a designer's guide. > > > > This is sci.electronics.,design. The people who post here do imagine that they design electronics, even clowns like you. > > The link you posted wasn't informative at the level you'd need if you wanted to make an informed decision about buying a multimeter, not that you;d know anything about that. > > > > > > "The latest UL standard for electrical test instruments is UL 61010B-1, which is a revision of 3111-1. It specifies the general safety requirements, such as material, design, and testing requirements, and the environmental conditions in which the standard applies. UL 3111-2-031 lists additional requirements for test probes. The requirements for hand-held current clamps, such as the current measuring portion of clamp meters, are included in UL 3111-2-032. > > > > > > > > UL standards are gradually being harmonized with similar international standards, such as those published by IEC. Until this is completed, there may be significant differences between each group's standards. For example, IEC 61010-1 2nd Edition includes requirements for voltage-measuring instruments in CAT IV environments. UL 61010B-1 doesn't." > > > > > > > > What Flyguy might be saying - if he knew what he was talking out - is that there are safety standards for multimeters. In the US they are published by the Underwriter > > > > Laboratory. > > > > > > I am WELL AWARE of UL and other testing labs. > > > > But not aware enough top pull out an actual standard that said anything specific. > > > > > > There are also international safety standards. > > > > > > > > https://www.nema.org/standards/international/the-iec-and-nema > > > > > > > > The International Electrotechnical Commission (IEC) headquartered in Geneva, Switzerland is the top level body. > > > > > > > > A chinese multi-meter might well not conform to an American Underwriters Laboratory standard, but will probably conform to the relevant IEC standard, which isn't going to be much different. > > > > > > Pure SPECULATION by Bozo completely UNVERIFIED by ANY facts whatsoever. But, why am I not surprised coming from Bill? > > > > Sewage Sweeper didn't produce any facts of his own - and never does. When he's exposed to them, he ignores them, but he'd great at recycling the abuse he gets, even when it is totally irrelevant. > > > No Bozo, it is YOU that doesn't ever produce any facts. You DO produce a bunch of lame excuses why you CAN'T produce the facts, though.This is your repeated claim. It's nonsense, but that doesn't stop you from churning it out.> > > > A cheap chinese meter might be truly cheap and nasty, and correspondingly dangerous, but anybody who sold it to you would risk being sued if it was. > > > > > > LOL! Just TRY suing a Chinese company - just TRY!! > > > > You don't sue the manufacturer. You sue the retailer who sold you a device that wasn't fit for the purpose for which it was advertised. > > Hey Bil, look where these meters come from: straight from China.But where were they bought? You sue the people who sold them to you, not the manufacturer.> > > > It's more likely to be cheap because it was produced in high volume, rather than because the manufacturer cut any corners. I've ran into one American instrument that didn't meet their published specifications, which is a slightly different kind of problem - it wasn't certainly wasn't cheap. > > > > > No, Bozo, they cut ALL KINDS of corners: https://www.youtube.com/watch?v=iGUiZT6kLDk > > A youtube video is evidence? > > Fucking YES!For an idiot like you.> > > Notice that this meter has NO certification marks. And for GOOD REASON: it would NEVER pass. > > > > Why should I care what some cheapskate idiot bought on E-bay? The device was CE marked, but the camera didn't linger longer to pick up the number of the relevant standard. > > WHY are you posting this bullshit, then? You obviously DO care!You will never know. It's not complicated, but it is more complicated than you could understand, even if you wanted to. -- Bill Sloman, Sydney
Reply by ●January 11, 20232023-01-11
On Monday, January 9, 2023 at 10:02:40 PM UTC-8, bill....@ieee.org wrote:> On Tuesday, January 10, 2023 at 3:11:41 PM UTC+11, Flyguy wrote: > > On Sunday, January 8, 2023 at 7:50:20 PM UTC-8, bill....@ieee.org wrote: > > > On Monday, January 9, 2023 at 5:47:17 AM UTC+11, Flyguy wrote: > > > > On Sunday, January 8, 2023 at 6:41:15 AM UTC-8, bill....@ieee.org wrote: > > > > > On Sunday, January 8, 2023 at 5:52:35 PM UTC+11, Flyguy wrote: > > > > > > On Saturday, January 7, 2023 at 11:31:33 AM UTC-8, Ed Lee wrote: > > > > > > > On Saturday, January 7, 2023 at 11:22:49 AM UTC-8, Fred Bloggs wrote: > > > > > > > > On Saturday, January 7, 2023 at 2:16:50 PM UTC-5, Ed Lee wrote: > > > > > > > > > On Saturday, January 7, 2023 at 11:10:02 AM UTC-8, Fred Bloggs wrote: > > > > > > > > > > On Saturday, January 7, 2023 at 1:42:05 PM UTC-5, Ed Lee wrote: > > > > > > > > > > > On Saturday, January 7, 2023 at 10:14:06 AM UTC-8, John Larkin wrote: > > > > > > > > > > > > On Sat, 7 Jan 2023 09:34:02 -0800 (PST), Fred Bloggs <bloggs.fred...@gmail.com> wrote: > > > > > > > > > > > > > > > > > > > > > > > > >On Saturday, December 31, 2022 at 1:19:58 PM UTC-5, Ed Lee wrote: > > > > > <snip> > > > > > > If you are going to be working on HV circuits (>240 V) ONLY use DMMs with a CAT certification (which cheap Chinese meters don't have). > > > > > > https://www.fluke.com/en-us/learn/blog/safety/multimeter-guide > > > > > > > > > > Which doesn't tell you much. > > > > > > > > It tells you everything you need to know to make a purchasing decision. This IS NOT a designer's guide. > > > > > > This is sci.electronics.,design. The people who post here do imagine that they design electronics, even clowns like you. > > > The link you posted wasn't informative at the level you'd need if you wanted to make an informed decision about buying a multimeter, not that you;d know anything about that. > > > > > > > > "The latest UL standard for electrical test instruments is UL 61010B-1, which is a revision of 3111-1. It specifies the general safety requirements, such as material, design, and testing requirements, and the environmental conditions in which the standard applies. UL 3111-2-031 lists additional requirements for test probes. The requirements for hand-held current clamps, such as the current measuring portion of clamp meters, are included in UL 3111-2-032. > > > > > > > > > > UL standards are gradually being harmonized with similar international standards, such as those published by IEC. Until this is completed, there may be significant differences between each group's standards. For example, IEC 61010-1 2nd Edition includes requirements for voltage-measuring instruments in CAT IV environments. UL 61010B-1 doesn't." > > > > > > > > > > What Flyguy might be saying - if he knew what he was talking out - is that there are safety standards for multimeters. In the US they are published by the Underwriter > > > > > Laboratory. > > > > > > > > I am WELL AWARE of UL and other testing labs. > > > > > > But not aware enough top pull out an actual standard that said anything specific. > > > > > > > > There are also international safety standards. > > > > > > > > > > https://www.nema.org/standards/international/the-iec-and-nema > > > > > > > > > > The International Electrotechnical Commission (IEC) headquartered in Geneva, Switzerland is the top level body. > > > > > > > > > > A chinese multi-meter might well not conform to an American Underwriters Laboratory standard, but will probably conform to the relevant IEC standard, which isn't going to be much different. > > > > > > > > Pure SPECULATION by Bozo completely UNVERIFIED by ANY facts whatsoever. But, why am I not surprised coming from Bill? > > > > > > Sewage Sweeper didn't produce any facts of his own - and never does. When he's exposed to them, he ignores them, but he'd great at recycling the abuse he gets, even when it is totally irrelevant. > > > > > No Bozo, it is YOU that doesn't ever produce any facts. You DO produce a bunch of lame excuses why you CAN'T produce the facts, though. > This is your repeated claim. It's nonsense, but that doesn't stop you from churning it out.LOL! Your reply doesn't have ANY facts in it!! Why am I not surprised, Bozo?> > > > > A cheap chinese meter might be truly cheap and nasty, and correspondingly dangerous, but anybody who sold it to you would risk being sued if it was. > > > > > > > > LOL! Just TRY suing a Chinese company - just TRY!! > > > > > > You don't sue the manufacturer. You sue the retailer who sold you a device that wasn't fit for the purpose for which it was advertised. > > > > Hey Bil, look where these meters come from: straight from China. > > But where were they bought? You sue the people who sold them to you, not the manufacturer.Good luck with that sorry plan. Do you have even ONE example where that has been successful, just ONE? I seriously DOUBT IT!> > > > > It's more likely to be cheap because it was produced in high volume, rather than because the manufacturer cut any corners. I've ran into one American instrument that didn't meet their published specifications, which is a slightly different kind of problem - it wasn't certainly wasn't cheap. > > > > > > > No, Bozo, they cut ALL KINDS of corners: https://www.youtube.com/watch?v=iGUiZT6kLDk > > > A youtube video is evidence? > > > > Fucking YES! > For an idiot like you.Completely unresponsive, Bozo.> > > > Notice that this meter has NO certification marks. And for GOOD REASON: it would NEVER pass. > > > > > > Why should I care what some cheapskate idiot bought on E-bay? The device was CE marked, but the camera didn't linger longer to pick up the number of the relevant standard. > > > > WHY are you posting this bullshit, then? You obviously DO care! > You will never know. It's not complicated, but it is more complicated than you could understand, even if you wanted to.Again, UNRESPONSIVE. It's NOT complicated, but you obviously have no reason.> > -- > Bozo Sloman, SydneyBozo's Sewage Sweeper
Reply by ●January 11, 20232023-01-11
On Wednesday, January 11, 2023 at 5:05:49 PM UTC+11, Flyguy wrote:> On Monday, January 9, 2023 at 10:02:40 PM UTC-8, bill....@ieee.org wrote: > > On Tuesday, January 10, 2023 at 3:11:41 PM UTC+11, Flyguy wrote: > > > On Sunday, January 8, 2023 at 7:50:20 PM UTC-8, bill....@ieee.org wrote: > > > > On Monday, January 9, 2023 at 5:47:17 AM UTC+11, Flyguy wrote: > > > > > On Sunday, January 8, 2023 at 6:41:15 AM UTC-8, bill....@ieee.org wrote: > > > > > > On Sunday, January 8, 2023 at 5:52:35 PM UTC+11, Flyguy wrote: > > > > > > > On Saturday, January 7, 2023 at 11:31:33 AM UTC-8, Ed Lee wrote: > > > > > > > > On Saturday, January 7, 2023 at 11:22:49 AM UTC-8, Fred Bloggs wrote: > > > > > > > > > On Saturday, January 7, 2023 at 2:16:50 PM UTC-5, Ed Lee wrote: > > > > > > > > > > On Saturday, January 7, 2023 at 11:10:02 AM UTC-8, Fred Bloggs wrote: > > > > > > > > > > > On Saturday, January 7, 2023 at 1:42:05 PM UTC-5, Ed Lee wrote: > > > > > > > > > > > > On Saturday, January 7, 2023 at 10:14:06 AM UTC-8, John Larkin wrote: > > > > > > > > > > > > > On Sat, 7 Jan 2023 09:34:02 -0800 (PST), Fred Bloggs <bloggs.fred...@gmail.com> wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > >On Saturday, December 31, 2022 at 1:19:58 PM UTC-5, Ed Lee wrote:<snip>> > But where were they bought? You sue the people who sold them to you, not the manufacturer. > > Good luck with that sorry plan. Do you have even ONE example where that has been successful, just ONE? I seriously DOUBT IT!It's standard doctrine. Your contract was with the retailer, not the manufacturer.> > > > > > It's more likely to be cheap because it was produced in high volume, rather than because the manufacturer cut any corners. I've ran into one American instrument that didn't meet their published specifications, which is a slightly different kind of problem - it wasn't certainly wasn't cheap. > > > > > > > > > No, Bozo, they cut ALL KINDS of corners: https://www.youtube.com/watch?v=iGUiZT6kLDk > > > > A youtube video is evidence? > > > > > > Fucking YES! > > > For an idiot like you. > > Completely unresponsive.I'm supposed to take your idiot delusions seriously?> > > > > Notice that this meter has NO certification marks. And for GOOD REASON: it would NEVER pass. > > > > > > > > Why should I care what some cheapskate idiot bought on E-bay? The device was CE marked, but the camera didn't linger longer to pick up the number of the relevant standard. > > > > > > WHY are you posting this bullshit, then? You obviously DO care! > > > > You will never know. It's not complicated, but it is more complicated than you could understand, even if you wanted to. > > Again, UNRESPONSIVE. It's NOT complicated, but you obviously have no reason.Nothing looks complicated to Sewage Sweeper - he can't understand anything complicated, so he just ignores it, and dreams up some fatuous delusion that suits his argument. -- Bill Sloman, Sydney
Reply by ●January 14, 20232023-01-14
John Larkin <jlarkin@highlandsnipmetechnology.com> wrote:> On Sun, 8 Jan 2023 19:02:15 -0000 (UTC), antispam@math.uni.wroc.pl > wrote: > > >John Larkin <jlarkin@highlandsnipmetechnology.com> wrote: > >> On Sat, 7 Jan 2023 01:04:32 -0000 (UTC), antispam@math.uni.wroc.pl > >> wrote: > >> > >> >Ed Lee <edward.ming.lee@gmail.com> wrote: > >> >> But not immediately. I tested 400V occasionally, but couple of them died while testing 12V. I am wondering it 400V weaken the meter. > >> > > >> >High voltage can destroy resistors, but this seem to be quite fast. > >> > > >> >> The old CenTech meters are 1000V, but the new models are 250V. Why even bother to have 50V more than the next range of 200V. Perhaps it's just same design with new label, when they got enough reports/complaints. > >> > > >> >Lot of folks live in countries where line voltage is 230V. So 50 volts > >> >makes a lot of difference. > >> > > >> >> I am wondering if it's worth picking up some of the older 1000V models off ebay. > >> > > >> >I know nothing about CenTech meters. But I have several "DT830B" > >> >meters. Available schematics shows 3 resistors in series for 1000V. > >> >My oldest one have 2 resistors. Newest one have single resistor. > >> >Standard miniature resistors are rated for 250V, one can get > >> >better ones, but I doubt that one can get cheaply 1000V capable > >> >ones. Still, meter is marked as 1000V DC, 700V AC (the same > >> >as old meters). > >> > >> They eliminated 0.2 cents worth of resistors. Ignore temperature and > >> voltage coefficient effects. Maybe some of that is mathed out? > >> > >> Chinese product prices ratchet towards cheap, and the specs ratchet > >> deep into the lies region. Chinese amps and volts and per cent are > >> about 10:1 off from SI standards. > > > >Well, the cheap "DT830B" were surprisingly accurate. I have > >used 4 to measure the same voltage. IIRC the differences > >were in last digit and did not exceed 2 counts. They were > >bought from different sources at different times, so it > >is unlikly to be the same error on all. And they agreed > >with better meter. Newest ones seem to have larger > >errors, but still well withing specs. > > > >AFAICS biggest problem with cheap meters are test leads, > >they tend to fail rather quickly. Second problem is > >main switch, which is formed from part of PCB. It > >seem to degrade with use. And failing switch can > >produce all kinds of wrong results. > > Why buy cheap junk test equipment?I would not lablel my "DT830B"-s as junk, they work well enough. As I wrote, they are accurate. They are small and light. And the measurement ranges are better suited to electronics that many more expensive meters (for example many meters lack 200uA range). I like ranges set by switch and lack of automatic turn-off (so meter does not turn off half into long measurement). Featurewise, I would like separate power switch, but that would be hard to add given compact form factor. Concerning test leads, when they fail I take new ones, that is minor annoyance. Basically it means that one has to factor cost of replacement leads to price of the meter. Concerning PCB switch, it means that meter is less durable than meters with real switch. OTOH looking at teardowns of various meters I saw no with real switch. Maybe there are some, but I do not expect to get meter with real switch below $60 (or should I write $600?). To put it differently, for simple measurements I do not see anything better, so why pay more? When I need better accuracy or need more than "DT830B" can do I use better meters (slightly better "DT9205A" or Aneng 8000 series). BTW: Some folks probably would say that Anengs are "cheap junk", they costed me below $20 per piece. Yet they have resolution better than much more expensive stuff. They look solid and people who tested them say they are solid.> Why buy cheap junk anything?I many cases buying a product is cheapest way to get info if it is worth anything. In bygone era one could relay on brands, but this is no longer the case, one can buy product from expensive brand and get exactly the same junk as cheap one. -- Waldek Hebisch
Reply by ●January 14, 20232023-01-14
On Sat, 14 Jan 2023 15:06:40 -0000 (UTC), antispam@math.uni.wroc.pl wrote:>John Larkin <jlarkin@highlandsnipmetechnology.com> wrote: >> On Sun, 8 Jan 2023 19:02:15 -0000 (UTC), antispam@math.uni.wroc.pl >> wrote: >> >> >John Larkin <jlarkin@highlandsnipmetechnology.com> wrote: >> >> On Sat, 7 Jan 2023 01:04:32 -0000 (UTC), antispam@math.uni.wroc.pl >> >> wrote: >> >> >> >> >Ed Lee <edward.ming.lee@gmail.com> wrote: >> >> >> But not immediately. I tested 400V occasionally, but couple of them died while testing 12V. I am wondering it 400V weaken the meter. >> >> > >> >> >High voltage can destroy resistors, but this seem to be quite fast. >> >> > >> >> >> The old CenTech meters are 1000V, but the new models are 250V. Why even bother to have 50V more than the next range of 200V. Perhaps it's just same design with new label, when they got enough reports/complaints. >> >> > >> >> >Lot of folks live in countries where line voltage is 230V. So 50 volts >> >> >makes a lot of difference. >> >> > >> >> >> I am wondering if it's worth picking up some of the older 1000V models off ebay. >> >> > >> >> >I know nothing about CenTech meters. But I have several "DT830B" >> >> >meters. Available schematics shows 3 resistors in series for 1000V. >> >> >My oldest one have 2 resistors. Newest one have single resistor. >> >> >Standard miniature resistors are rated for 250V, one can get >> >> >better ones, but I doubt that one can get cheaply 1000V capable >> >> >ones. Still, meter is marked as 1000V DC, 700V AC (the same >> >> >as old meters). >> >> >> >> They eliminated 0.2 cents worth of resistors. Ignore temperature and >> >> voltage coefficient effects. Maybe some of that is mathed out? >> >> >> >> Chinese product prices ratchet towards cheap, and the specs ratchet >> >> deep into the lies region. Chinese amps and volts and per cent are >> >> about 10:1 off from SI standards. >> > >> >Well, the cheap "DT830B" were surprisingly accurate. I have >> >used 4 to measure the same voltage. IIRC the differences >> >were in last digit and did not exceed 2 counts. They were >> >bought from different sources at different times, so it >> >is unlikly to be the same error on all. And they agreed >> >with better meter. Newest ones seem to have larger >> >errors, but still well withing specs. >> > >> >AFAICS biggest problem with cheap meters are test leads, >> >they tend to fail rather quickly. Second problem is >> >main switch, which is formed from part of PCB. It >> >seem to degrade with use. And failing switch can >> >produce all kinds of wrong results. >> >> Why buy cheap junk test equipment? > >I would not lablel my "DT830B"-s as junk, they work well enough. >As I wrote, they are accurate. They are small and light. >And the measurement ranges are better suited to electronics >that many more expensive meters (for example many meters lack >200uA range). I like ranges set by switch and lack of automatic >turn-off (so meter does not turn off half into long measurement). >Featurewise, I would like separate power switch, but that would >be hard to add given compact form factor. > >Concerning test leads, when they fail I take new ones, that is >minor annoyance. Basically it means that one has to factor >cost of replacement leads to price of the meter. Concerning >PCB switch, it means that meter is less durable than meters with >real switch. OTOH looking at teardowns of various meters I >saw no with real switch. Maybe there are some, but I do not >expect to get meter with real switch below $60 (or should >I write $600?). > >To put it differently, for simple measurements I do not see >anything better, so why pay more? When I need better accuracy >or need more than "DT830B" can do I use better meters >(slightly better "DT9205A" or Aneng 8000 series). > >BTW: Some folks probably would say that Anengs are >"cheap junk", they costed me below $20 per piece. >Yet they have resolution better than much more expensive >stuff. They look solid and people who tested them say >they are solid. > >> Why buy cheap junk anything? > >I many cases buying a product is cheapest way to get info >if it is worth anything. In bygone era one could relay >on brands, but this is no longer the case, one can buy >product from expensive brand and get exactly the same >junk as cheap one.I don't understand spending hours to save a few dollars and maybe get something flakey. Some people are just obcessive about saving money. They clip coupons, search for deals, buy and return stuff. Fluke and Extech and Rigol are good.
Reply by ●January 14, 20232023-01-14
On Saturday, January 14, 2023 at 7:06:49 AM UTC-8, anti...@math.uni.wroc.pl wrote:> John Larkin <jla...@highlandsnipmetechnology.com> wrote: > > On Sun, 8 Jan 2023 19:02:15 -0000 (UTC), anti...@math.uni.wroc.pl > > wrote: > > > > >John Larkin <jla...@highlandsnipmetechnology.com> wrote: > > >> On Sat, 7 Jan 2023 01:04:32 -0000 (UTC), anti...@math.uni.wroc.pl > > >> wrote: > > >> > > >> >Ed Lee <edward....@gmail.com> wrote: > > >> >> But not immediately. I tested 400V occasionally, but couple of them died while testing 12V. I am wondering it 400V weaken the meter. > > >> > > > >> >High voltage can destroy resistors, but this seem to be quite fast. > > >> > > > >> >> The old CenTech meters are 1000V, but the new models are 250V. Why even bother to have 50V more than the next range of 200V. Perhaps it's just same design with new label, when they got enough reports/complaints. > > >> > > > >> >Lot of folks live in countries where line voltage is 230V. So 50 volts > > >> >makes a lot of difference. > > >> > > > >> >> I am wondering if it's worth picking up some of the older 1000V models off ebay. > > >> > > > >> >I know nothing about CenTech meters. But I have several "DT830B" > > >> >meters. Available schematics shows 3 resistors in series for 1000V. > > >> >My oldest one have 2 resistors. Newest one have single resistor. > > >> >Standard miniature resistors are rated for 250V, one can get > > >> >better ones, but I doubt that one can get cheaply 1000V capable > > >> >ones. Still, meter is marked as 1000V DC, 700V AC (the same > > >> >as old meters). > > >> > > >> They eliminated 0.2 cents worth of resistors. Ignore temperature and > > >> voltage coefficient effects. Maybe some of that is mathed out? > > >> > > >> Chinese product prices ratchet towards cheap, and the specs ratchet > > >> deep into the lies region. Chinese amps and volts and per cent are > > >> about 10:1 off from SI standards. > > > > > >Well, the cheap "DT830B" were surprisingly accurate. I have > > >used 4 to measure the same voltage. IIRC the differences > > >were in last digit and did not exceed 2 counts. They were > > >bought from different sources at different times, so it > > >is unlikly to be the same error on all. And they agreed > > >with better meter. Newest ones seem to have larger > > >errors, but still well withing specs. > > > > > >AFAICS biggest problem with cheap meters are test leads, > > >they tend to fail rather quickly. Second problem is > > >main switch, which is formed from part of PCB. It > > >seem to degrade with use. And failing switch can > > >produce all kinds of wrong results. > > > > Why buy cheap junk test equipment? > I would not lablel my "DT830B"-s as junk, they work well enough. > As I wrote, they are accurate. They are small and light. > And the measurement ranges are better suited to electronics > that many more expensive meters (for example many meters lack > 200uA range). I like ranges set by switch and lack of automatic > turn-off (so meter does not turn off half into long measurement). > Featurewise, I would like separate power switch, but that would > be hard to add given compact form factor.The CenTech meter is almost identical but with a power switch. However, the switch is really small and unreliable. I am thinking about adding an external switch. I want auto-off after 24 hours. Sometimes, i left it on for days.
