Resistors SMD 0...000

[Nusa]

https://en.wikipedia.org/wiki/Real_versus_nominal_value

[Jwillis]

 Chip resistors (RSMD) if printed with a code will have an R used as a decimal. So a 50mOhm will be coded 0R05m or a 5mOhm will be coded 0R005.If its coded 0 or 0000 its considered a jumper.If it measures less than 1milliohm it is considered to be zero and with be marked as such.If no markings are on the chip it will be on the reel and datasheet.All this can be found under the Global part number or the 12NC code rules.

[tigr]

I measured the green resistor with three zeros.
Clearly 0,005 Ohm. It means they have the resistance set by the manufacturer, depending on the marking.
Thank you all for the helpful information.

[Jwillis]

RSMD can be green, red ,blue,brown or black.The color doesn't matter. If its marked as 0...000 its considered as a jumper or 0 ohm.

[tigr]

Did not anyone measure such resistors?

[tautech]

Did not anyone measure such resistors?

Don't need to !

If my 0, 000 or whatever 0805's are needed for other than 'signal path' use and I'm concerned about current I'll use a wire jumper instead !

[tigr]

It seems that they still differ in resistance. It seems to me, depending on the type of resistor, they have a fixed resistance. And this has its own logic. Regarding very low  resistances, there is a completely different technology.

[tigr]

We can draw definite conclusions. For some exceptions, all the resistors have basically a resistance of 0.01Om. To eliminate the error, the measurements were carried out by two tweezers with a resolution of 0.001 Ohm.
All measurements were done without removing the resistors.
Once again, thank you all.

[wraper]

We can draw definite conclusions. For some exceptions, all the resistors have basically a resistance of 0.01Om. To eliminate the error, the measurements were carried out by two tweezers with a resolution of 0.001 Ohm.
All measurements were done without removing the resistors.
Once again, thank you all.

First of all, you need 4 wire measurement to remotely precisely measure such resistance. Secondly, meter on the picture is something I would not trust, especially for such demanding measurments.

[tigr]

Both tweezers have a 4-wire measurement circuit. They are designed for in-circuit measurement of R and ESR. They have a low measuring voltage.

[BravoV]

First of all, you need 4 wire measurement to remotely precisely measure such resistance. Secondly, meter on the picture is something I would not trust, especially for such demanding measurments.

Op is well known troll, just read his previous threads/posts, as he doesn't even have any idea what a 4 wires measurement does, and keep posting and mumbling on how accurate and "conclusive" of his sub 10 mili Ohm measurements with his "elite" measurement meters (plural). 

[chrisl]

Here is the datasheet for 0 ohm jumpers from KOA.
Regardless of the marking (no marking, 0 or 000) of the jumpers the resistance is  50 m ohm max for all the jumpers. 

[tigr]

I ignore people who often use the word troll.

[tigr]

BravoV
And now, if you're a man, you can apologize for your words.

[wraper]

Both tweezers have a 4-wire measurement circuit. They are designed for in-circuit measurement of R and ESR. They have a low measuring voltage.

They are not real 4 wire. Yes there can be 4 wires till the contacts which helps to mitigate parasitics till the contacts but then there are only 2 contacts connecting to the part. Therefore this meter cannot subtract connection resistance from actual component resistance.

[wraper]

BravoV
And now, if you're a man, you can apologize for your words.

Oh, reading of 1 last digit of resolution. Shuld be accurate.

[tigr]

No problems.

[Brumby]

We can draw definite conclusions.
blah blah blah blah blah blah blah blah blah blah
Once again, thank you all.

There is someone I have worked with that does this exact thing.

They make a statement - an absolute statement, fail to back it up with demonstrable facts and/or accepted processes, fill in the empty space with confidently presented babble and finish by saying "Case closed!".  All the while expecting their audience to accept what is said without question.

They don't convince me - and neither do you.  You may be able to "draw definite conclusions" - but I'm not seeing it.

The content of your claims seem "off" to me and the style of your argument makes me wonder if you really understand the considerations that need to be taken for such low resistance measurements.  I also don't see any concrete evidence of 4 wire measurement either.

The Atlas ESR60 certainly isn't a 4 wire device, nor is the component tester.  So what about the tweezer meter ... is that 4 wire?

Also, you claim a resolution of 0.001 ohm - but what is its accuracy?

[tigr]

The Atlas ESR60 certainly isn't a 4 wire device, nor is the component tester.  So what about the tweezer meter ... is that 4 wire?

Interesting.

[wraper]

No problems.

There is one serious problem. Even not considering varying connection resistance, HB-14 has +/- 20 digit accuracy in this range.

[wraper]

The Atlas ESR60 certainly isn't a 4 wire device, nor is the component tester.  So what about the tweezer meter ... is that 4 wire?

Interesting.

Not interesting, because there is no 4 wire connection to the device under test . All it compensates is varying inductance and capacitance of the wires when you move them.

[tigr]

I'll have to call an arbitrator.
LCR Pro1.

[Brumby]

The Atlas ESR60 certainly isn't a 4 wire device,

Interesting.

My apologies.  But I had to go hunting to find ANY reference to that unit being 4 wire.  Even Peak don't mention it in their product spiel.

It seems it is 4 wire measurement capable according to this: https://nz.rs-online.com/web/p/lcr-meters/6660908/

[wraper]

I'll have to call an arbitrator.
LCR Pro1.

LOL, you can call as many non suitable meters as you want. To claim accurate measurment you need to use a proper multimeter or LCR meter with 4 wire measurment, and which is accurate enough in such low resistance range. And still that would only result in measurement for one particular resistor from particular batch. No conclusions can be made about anything in general. For that you would need to buy tons of different resistors from at least hundreds of batches.

[Monkeh]

Alternatively, simply accept their non-zero resistance and believe the datasheet claims (which are typically <50mohm).

If you happen to have some of that perfect zero-resistance jumper wire, use that. Clearly superior - I don't know why I use 25mm² tails for 100A supplies when small wire links are 0.000ohm.