Timeline for How to measure a resistance very accurately? [closed]
Current License: CC BY-SA 3.0
21 events
| when toggle format | what | by | license | comment | |
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| Mar 6, 2017 at 2:11 | history | closed |
Brian Carlton Wesley Lee Voltage Spike♦ ThreePhaseEel uint128_t |
Not suitable for this site | |
| Mar 4, 2017 at 21:14 | review | Close votes | |||
| Mar 6, 2017 at 2:14 | |||||
| Mar 4, 2017 at 20:58 | comment | added | Brian Carlton | I'm voting to close this question as off-topic because trying to do something not necessary and not possible. See comments already posted. | |
| Aug 16, 2016 at 23:30 | answer | added | F_Schro | timeline score: 0 | |
| Jan 1, 2016 at 0:05 | vote | accept | user16307 | ||
| Nov 6, 2013 at 13:32 | comment | added | Olin Lathrop | -1 for leading everyone on a wild goose chase. Go look up something called "significant digits". Several people wasted time replying to your absurd accuracy requirement because you couldn't be bothered to write a number properly. | |
| Nov 6, 2013 at 1:02 | answer | added | The Photon | timeline score: 5 | |
| Nov 5, 2013 at 21:08 | history | edited | JYelton | CC BY-SA 3.0 |
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| Nov 5, 2013 at 13:39 | comment | added | Pete Becker | @user16307 - if the requirement is 0.4%, then the value 300.8974083 is deep into false precision. Everything to the right of the leftmost 8 is nonsense. | |
| Nov 5, 2013 at 13:05 | answer | added | Olin Lathrop | timeline score: 17 | |
| Nov 5, 2013 at 12:00 | comment | added | JIm Dearden | Every resistor I'm familiar with has a temperature coefficient - measuring to this degree of accuracy would only be valid at one temperature. The moment you pass any current through the resistor it would change its value. | |
| Nov 5, 2013 at 11:58 | comment | added | user16307 | accuracy must be 0.4 % 2 ohms for 250 for instance. should i use Wheatstone? | |
| Nov 5, 2013 at 11:52 | comment | added | RedGrittyBrick | Unless I knew what accuracy was needed (and why), I'd just write down "300∓10%" and move on. | |
| Nov 5, 2013 at 11:49 | comment | added | user16307 | I dont know how they measured it before me. I just need an accurate method. they re suggesting wheatestone bridge but for measuring 250 ohm resistor what resistances and variable resistance is good to use for the bridge? | |
| Nov 5, 2013 at 11:48 | comment | added | RedGrittyBrick | @Tut: I suspect someone divided two lower precision numbers in Windows calc and wrote down the result without considering how meaningless those last digits were ;-) | |
| Nov 5, 2013 at 11:45 | comment | added | Tut | How was the number 300.8974083 obtained? | |
| Nov 5, 2013 at 11:31 | comment | added | RedGrittyBrick | Let me put it another way: if your nominal 300.8974083 ohm resistor had an actual resistance of only 300.8973001 ohms, exactly what bad consequences would occur? Can you describe the problem that would arise? | |
| Nov 5, 2013 at 11:18 | answer | added | RedGrittyBrick | timeline score: 2 | |
| Nov 5, 2013 at 10:55 | comment | added | user16307 | yes as much as possible I only have a multimeter and can buy some resistances. | |
| Nov 5, 2013 at 10:42 | comment | added | RedGrittyBrick | What application needs 0.000001% accuracy? | |
| Nov 5, 2013 at 10:35 | history | asked | user16307 | CC BY-SA 3.0 |