Author Topic: I'm looking for a cheap multimeter/ohmmeter that go into the miliohm range...  (Read 5833 times)

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Offline LUEshiTopic starter

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So yeah I am looking for some kind of device that allows me to measure down to the miliohm range for a personal project of mine. It doesn't have to be very precise it's just that the multimeter I have can only go down to .1 ohm and aren't very reliable down in that range. Does anyone have anything to recommend?
 


Offline Rick Law

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I do recall Franky here on wrote something about carrying a kit for milli-ohm meter.  I can't find the link for that post.  I think Franky's forum ID is ILoveElectronics.  Perhaps you can PM him or Franky can put in a note here.

I got my DMM (UT61e) from him, great service.
 

Offline iloveelectronics

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I do recall Franky here on wrote something about carrying a kit for milli-ohm meter.  I can't find the link for that post.  I think Franky's forum ID is ILoveElectronics.  Perhaps you can PM him or Franky can put in a note here.

I got my DMM (UT61e) from him, great service.

Not sure if the OP is looking for this as it sounds more like he/she is looking for a multimeter with milliohm capability, but here's the link to the milliohm meter kit: https://www.eevblog.com/forum/buysellwanted/fs-milliohmvoltage-meter-kit/msg447327/#msg447327

I still have a few sets of these.



My email address: franky @ 99centHobbies . com
My eBay store: http://stores.ebay.com/99centhobbies
 

Offline Wytnucls

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« Last Edit: April 30, 2015, 05:10:04 am by Wytnucls »
 

Offline LUEshiTopic starter

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wow, thank you for all the quick reply guys. I will look these up and pick out one of them, I'm considering a kit.
 

Online Gyro

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I've always thought the Maxim Milliohm meter adapter App Note was a pretty elegant design - of course you still need a basic multimeter to use it. You can use cheap Kelvin probes to get accurate results. I built one years ago and am still on the original batteries.

It's a Maxim app note, but of course you can use any suitable reference and Opamp.

http://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CD4QFjAA&url=http%3A%2F%2Fwww.wentztech.com%2Fradio%2Fresources%2FProjects%2FAN106.pdf&ei=RBFCVfTcJIbZaozBgYAD&usg=AFQjCNHFrTMOWC7ulySX1TP-KLwZkt0Pfw&bvm=bv.92189499,d.d24
Best Regards, Chris
 

Offline robrenz

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Get yourself some capacitance, inductance, and esr capability in the process.  The DE-5000 can be had for roughly $130.00. The video shows its performance in the series resistance mode on a capacitor to measure esr.
Because it uses AC excitation of the DUT it eliminates thermal emf errors that many of the other units don't unless they have offset compensated Ohms feature.



Offline michael.hill

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<offtopic>
Y Helo Thar, LUEshi!
</offtopic>
 

Offline LUEshiTopic starter

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<offtopic>
Y Helo Thar, LUEshi!
</offtopic>

the reach of this community is incredible.
 

Offline AG6QR

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If you have access to a bench power supply, or any other source of constant current (an LM317 regulator in constant current mode, for example) just pass a current through the item you're measuring, and measure the voltage across it.  For example, at a current of 1 amp, a meter set on its millivolt range will give the value of the resistance in milliohms.

In fact, the current doesn't necessarily need to be very well-regulated, if you have a way of measuring it precisely with one meter while you measure voltage with another.  Ohm's law is a wonderful thing.
 

Offline Lightages

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I second robrenz's recommendation for the DE5000. I also recently purchased a used Keithley 197 that is a very nice benchtop multimeter with milliohm resolution.
 

Offline robrenz

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If you have access to a bench power supply, or any other source of constant current (an LM317 regulator in constant current mode, for example) just pass a current through the item you're measuring, and measure the voltage across it.  For example, at a current of 1 amp, a meter set on its millivolt range will give the value of the resistance in milliohms.

In fact, the current doesn't necessarily need to be very well-regulated, if you have a way of measuring it precisely with one meter while you measure voltage with another.  Ohm's law is a wonderful thing.

This does not take into account thermal EMF errors. You need to average 2 readings one of which has the drive current reversed. Or measure the voltage drop without current and subtract it from the voltage drop with current (offset compensated reading)


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