tag:blogger.com,1999:blog-36956433.post3570126047065430861..comments2024-02-08T06:47:40.662-06:00Comments on DIY Audio Projects - Hi-Fi Blog for DIY Audiophiles: Simple Low Resistance MeasurementdiyAudioProjects.comhttp://www.blogger.com/profile/02982731963250878024noreply@blogger.comBlogger18125tag:blogger.com,1999:blog-36956433.post-77439662904507317352021-09-18T01:50:43.574-05:002021-09-18T01:50:43.574-05:00Resistance measurements are much related to impeda...Resistance measurements are much related to impedance and instrument overall opposition to charges. Only a calibrated multimeter can do it well. meterreviewshttps://meterreviews.com/how-to-measure-resistance/noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-33315211205102460832021-07-04T09:44:52.012-05:002021-07-04T09:44:52.012-05:00A clever way to make a low resistance measurement....A clever way to make a low resistance measurement. Much cheaper than having to buy a specialized multimeter for the job. All the best.Samhttps://www.se-instruments.com/best-multimeter-for-the-money/noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-3128499619436514902021-06-24T04:32:13.194-05:002021-06-24T04:32:13.194-05:00Very Helpful article, ThanksVery Helpful article, ThanksSofia Joyhttps://multimetertools.com/noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-90210754564199462672021-05-24T12:52:31.522-05:002021-05-24T12:52:31.522-05:00Thank you.. I have apply it , and it worked succes...Thank you.. I have apply it , and it worked successfully Natash Lyonshttps://getmultimeter.com/noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-1802595321452635562019-08-22T21:54:45.829-05:002019-08-22T21:54:45.829-05:00At point m the meaured resistance it is higher tha...At point m the meaured resistance it is higher than the actual value at and at point n it is lower than the actual value 7:20Shaonhttps://www.toolsguides.comnoreply@blogger.comtag:blogger.com,1999:blog-36956433.post-57802102214908286632018-07-04T04:05:18.818-05:002018-07-04T04:05:18.818-05:00thank you for this great article , your post is a ...thank you for this great article , your post is a source of inspiration for meMichaelhttps://bestmultimeter.reviews/noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-75523922114500686272018-04-01T15:13:33.163-05:002018-04-01T15:13:33.163-05:00if i use 3 AA then what watt rating should the 12 ...if i use 3 AA then what watt rating should the 12 ohm resistor be?Anonymoushttps://www.blogger.com/profile/09391167009801699755noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-71986529250532080192017-10-26T12:01:15.610-05:002017-10-26T12:01:15.610-05:00I was searching depth information about low resist...I was searching depth information about low resistance measurement. Because, I need this for my assignment. Really, you explain here quite well.kelliohttps://bestmultimeterreviews.org/noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-66926079027273042432015-10-27T08:33:09.854-05:002015-10-27T08:33:09.854-05:00Thanks for the info.Thanks for the info.Jakehttp://jakebigdawg.comnoreply@blogger.comtag:blogger.com,1999:blog-36956433.post-41962710653680994032015-09-16T03:19:20.290-05:002015-09-16T03:19:20.290-05:00Thank your tips it very easy to understand and I h...Thank your tips it very easy to understand and I have used successfully.Minhhttp://multimeterexpert.com/noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-74597033374499348192014-05-30T02:17:29.375-05:002014-05-30T02:17:29.375-05:00The many thousand dollar Hickock the USAF gave me ...The many thousand dollar Hickock the USAF gave me to work on RADAR in the university of South East Asia, Class of '74 was a four wire unit. Two 8" 90* analog dials so I could match "G-lines" to .0001 ohm in F4's. They couldn't find "home" without it and AAA was homed in on RADAR signals. A Non A Moosenoreply@blogger.comtag:blogger.com,1999:blog-36956433.post-80452230465109874762014-01-20T10:06:03.053-06:002014-01-20T10:06:03.053-06:00Anonymous 6:32 AM, January 16, 2014:
"The LM3...Anonymous 6:32 AM, January 16, 2014:<br />"The LM317 is rated at 1.5 amps but trying to push 1 A"<br /><br />Actually the LM317 voltage regulator is set to deliver 100 mA of test current, not 1A.<br /><br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-36956433.post-45351791297485308432014-01-16T06:32:52.774-06:002014-01-16T06:32:52.774-06:00The Kelvin resistance method assumes the constant ...The Kelvin resistance method assumes the constant current source is really constant throughout the measurement. The LM317 is rated at 1.5 amps but trying to push 1 A with unspecified power source without proper heat sink will not get the actual current. Better use the old fashion method of having a current meter (ammeter) in the circuit, so you will know the current at all time. You will need two DMM, but DMM are so cheap now days.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-36956433.post-55203901659281719772012-06-16T11:17:41.029-05:002012-06-16T11:17:41.029-05:00Kelvin clips are easy to cobble. Cut off the meta...Kelvin clips are easy to cobble. Cut off the metal pivot ears from standards clips and replace them with a small rod of plastic, thus insulating the two clip halves. Pull the jaws closed with a short length of rubber tube. Then wire one jaw to the current source and the other to the DVM. Presto! Now you are measuring low resistances accurately!Bobhttps://www.blogger.com/profile/09726805396038087981noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-4958274234954658472010-08-09T16:20:53.594-05:002010-08-09T16:20:53.594-05:00And, as I have experienced many times, even when y...And, as I have experienced many times, even when you null out the meter leads resistance, you still have a tough job ahead. Reason is: the wires are stranded. This means there are numerous smaller diameter solid wires connected in parallel, inside the insulation of the lead. These wires touch each other many times throughout the space inside the insulation, with the result that they have the effect of numerous very low value resistances connected in series and parallel, between the test probes and the meter plugs.<br /><br />Why is that a problem? As you pick up the test probes and apply them to the resistance you wish to measure, all those series-parallel combinations change many times with each minute movement of the leads! That means the net resistance of the lead wires will also change, making the measurements you took to cancel out the lead's resistance a waste of time; as soon as you move the leads, the resistance changes.<br /><br />The only good way to deal with this is to use some kind of four-wire method, where a constant current source supplies current to the resistance being tested though one set of stable wires, while the voltage across the resistance is measured with a totally separate pair of wires, thus, the voltage reading will not be affected by the very small resistance of the voltmeter's leads, because the drive current does not flow through them. There are many examples of this available on the internet; they show clever ways to do this without a great deal of trouble or expense.Larry Holmes aka "kosimov"noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-69383440727973241252008-11-29T10:10:00.000-06:002008-11-29T10:10:00.000-06:00Yes, as noted, that will give you an improved read...Yes, as noted, that will give you an improved reading, but still not accurate especially when you are trying to measure very low resistance.diyAudioProjects.comhttps://www.blogger.com/profile/02982731963250878024noreply@blogger.comtag:blogger.com,1999:blog-36956433.post-41333256349718424252008-11-28T09:03:00.000-06:002008-11-28T09:03:00.000-06:00@MartinYes and no. There is no way that 1 foot of...@Martin<BR/><BR/>Yes and no. There is no way that 1 foot of test leads have a resistance of .4 ohms, not even if they were the size of a hair. The reason is that the test current produced by a meter is to small to measure low resistance accurately. Subtracting that amount helps, but it is still not accurate.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-36956433.post-23302246672830172442008-11-27T19:26:00.000-06:002008-11-27T19:26:00.000-06:00When measuring a resistance with a digital multime...When measuring a resistance with a digital multimeter, one of the most common mistakes made is not factoring in the resistance of the meter's leads. This will produce a false higher reading. By first clipping the two leads together you can measure the resistance of the meter, for example my multimeter lead resistance is 0.4 ohms. Then when you measure the actual resistance of interest, remember to subtract the lead's resistance to get the correct result.Anonymousnoreply@blogger.com