Good multimeter to buy - Page 1
Forum section: electronics / beginners

author: german77
author_rank: Regular Contributor
timestamp: June 01, 2019, 01:41:34 am
content: I have been searching for a good multimeter in the range of $50-$250 US dollars that suits my needs. But I can't found one that suits all my needs.I need to measure very low resistances below 0.1 ohms. Diode check above 5v. And currents in the order of nA. And It must has at least 10M ohm input impedance. I mostly use it to fix and test devices that use 3.3v up to 60v. Where a cheap multimeter can't test zeners, shunt resistors, coil resistances, measure low currents, or simply the simple act of measuring changes the way the circuit behaves.Fluke multimeters at least the affordable ones don't meet my requirements as they are designed for high voltage applications.The 121GW multimeter meets everything I need, but the total price to ship to Mexico is $385 which is way to high compared to the $180 price shown in the website.Other brands have almost the same specs as fluke. Do anyone know a multimeter that would be suitable for me? or a seller of 121GW that will ship to Mexico and not double the price?

author: ejeffrey
author_rank: Super Contributor
timestamp: June 01, 2019, 03:20:12 am
content: If you need to measure below .1 ohm I highly recommend a bench meter with 4 wire ohms and some Kelvin lead clips. You can do it with a regular dmm and zero offset correction but it is hard to get the probe contact repeatability much better than that. I really want a handheld dmm with 4 wire ohms mode, but I have never seen one.The diode thing really narrows it down. Consider just making an external diode probe from a battery and a resistor. It is not as convenient as a built in mode of your meter but will really open up your choices.

author: Electro Detective
author_rank: Super Contributor
timestamp: June 01, 2019, 04:21:17 am
content: Consider getting two affordable meters that have the features you need amongst them.The 'All In One' concept has never worked for me and or the pricessuited rich tech companies purses

author: bob91343
author_rank: Super Contributor
timestamp: June 01, 2019, 04:26:44 am
content: I suggest you check out the HP 412A. It meets most of your requirements and should be available for not too much. It's a boat anchor, using tubes. The low Ohms range has a center scale of 1 Ohm. It will measure current down to 1 microamp full scale I think.If you find one make sure it comes with probes. They are NOT just simple test leads.There is, as far as I know, nothing much for testing zener diodes. You will need an external power supply and a series resistor but that's easy enough.Some of the bench type digital units are good too, and are solid state.

author: radiolistener
author_rank: Super Contributor
timestamp: June 01, 2019, 05:15:49 am
content: UNI-T UT61E - cheap work horse for home lab.Also you can look at Brymen BM867, it is more safe.

author: MosherIV
author_rank: Super Contributor
timestamp: June 01, 2019, 09:46:27 am
content: HiThe 2 requirments that will be difficult to satify areMeasure resistance down at 0.1Measure diode voltage upto 5V (for tester zeners)I do not think there are any dmm that can do the latter.There are a number of projects or kits on the internet that do a device that measures diode voltage and zener voltage. I think some even go upto 20VAs ejeffery suggested, to measure low resistance accuractly, you will need a dmm with 4 wire measurement. As far as I know, only bench meters have this feature.You can either look out for used ones on ebay.Or cheap brands to look atGW InstekBK precisionI am not a fan of Rigol, Vichi or Uni-T bench metersThe suggestion for 2 dmm is also a good idea but having 2 may not satisfy your original requirements.I do not think the ut61e can do either of the difficult requirements. I have one, the diode testing voltage is only 3V. Like all hand held dmms, they are not good at resistance below a few

author: xavier60
author_rank: Super Contributor
timestamp: June 01, 2019, 10:35:03 am
content: Because 4 leads are needed to properly measure low resistances, 2 of those leads can be from a bench supply precisely set to 1 amp in CC mode. The mV range on most DMMs will give an accurate equivalent reading in milliohms with 100µΩ resolution.I test a lot of shunt resistors in motor controllers. The bench supply leads can be clipped to any convenient locations that pass current through the shunt. The the voltage is measured directly at the shunt resistor ends.

author: Gyro
author_rank: Super Contributor
timestamp: June 01, 2019, 12:40:41 pm
content: Quote from: xavier60 on June 01, 2019, 10:35:03 am^^ What he said. I built a 4 lead low ohms adapter with accurate switchable current ranges (1mA to 1A) but any current source, including a reasonably accurate bench PSU will do the job fine.Use the same approach with Zeners - a bench PSU and a suitable chosen series resistor to limit the Zener dissipation is fine. Don't rely on just the PSU current limit for Zeners - most PSUs have sufficient output capacitance to put out a nasty current spike into the junction when first connected so use the series resistor.

author: strawberry
author_rank: Super Contributor
timestamp: June 02, 2019, 10:30:12 am
content: 121GWwelectron.comdeutsche postwoldwide free shipping 5..30daystax may apply?

author: mqsaharan
author_rank: Regular Contributor
timestamp: June 02, 2019, 12:15:33 pm
content: Quote from: ejeffrey on June 01, 2019, 03:20:12 amIf you really want one, may I suggest to look at some of Gossen's offerings like:https://www.gossenmetrawatt.com/english/produkte/metrahit-im-xtra.htmTechnical Data for IM-Xtrahttps://www.gossenmetrawatt.com/resources/tt/metrahit-im-xtra/metrahit-im-xtra-edrive-db_gb.pdfhttps://www.gossenmetrawatt.com/english/produkte/metrahit27m.htmTechnical Data for 27M and 27Ihttps://www.gossenmetrawatt.com/resources/tt/hit27/metrahit-27-db_gb.pdfhttps://www.gossenmetrawatt.com/english/produkte/metrahit27i.htmI am not sure about the price and availability of any of these in USA.Sorry, my post is not very helpful for OP.

author: bob91343
author_rank: Super Contributor
timestamp: June 02, 2019, 04:42:53 pm
content: I easily built a 4 wire Ohmmeter with a normal DMM and a wall wart. I can read, I think, 0.01 Ohm with it.It's simply a current source with an LM317 or something. Google DIY low resistance meter.

author: ledtester
author_rank: Super Contributor
timestamp: June 03, 2019, 03:14:21 pm
content: Quote from: bob91343 on June 02, 2019, 04:42:53 pmAlso search for milliohm meter project on youtube.

author: ejeffrey
author_rank: Super Contributor
timestamp: June 03, 2019, 08:10:20 pm
content: Quote from: mqsaharan on June 02, 2019, 12:15:33 pmNice. Too rich for my blood, but I'm glad they exist. I will probably continue to make do with an external current source and the millivolts range unless I find a great deal on such a meter.

author: n5al
author_rank: Contributor
timestamp: June 09, 2019, 10:30:49 am
content: Quote from: german77 on June 01, 2019, 01:41:34 amI share your pain about high shipping costs to Mexico. That's why I always make a list of things to buy during the couple of trips I make to the US every year.Surprisingly, on the EEVBlog store, it shows charges are only about AUD$ 30 to ship a 121GW multimeter to here in Guadalajara. I suppose Aduanas would try to collect the additional 16% IVA before delivery. Maybe I'm missing something here, because I really expected to see a MUCH high shipping cost, like the one you mentioned in your post.

author: Connecteur
author_rank: Frequent Contributor
timestamp: July 15, 2019, 01:23:30 pm
content: I was intrigued by the multimeters on AliExpress that sell in the $1.70 range, so I ordered some. They work fine, and accurate as far as I've tested them, but I can't see any reason to buy these things, when for a dollar or two more, you can get a much nicer one.The last few corners have been cut making these multimeters as cheap to build as possible. The test leads are thin, flimsy and soldered-in. The plastic case has sharp edges that they didn't bother to grind off, and the cover is very difficult to open. Yes, it has a flip-cover for that price. Still not worth buying in my opinion.

author: radiolistener
author_rank: Super Contributor
timestamp: July 15, 2019, 02:19:31 pm
content: Quote from: Connecteur on July 15, 2019, 01:23:30 pmthey are intended to measure battery in your car or just to check your bulb lamp for internal break. If you're want to see the real voltage, or to perform more precise measurements, you're needs a good multimeter.

author: GeorgeOfTheJungle
author_rank: Super Contributor
timestamp: July 15, 2019, 02:56:36 pm
content: Quote from: Electro Detective on June 01, 2019, 04:21:17 amTwo or more... if need be

author: rsjsouza
author_rank: Super Contributor
timestamp: July 15, 2019, 04:17:24 pm
content: I also recommend going for a bench multimeter given the specifications for very low resistance modes.For the high voltage diode test, however, you can get by with simple circuits around the web and/or the small testers from China.If bench meters are hard to find, I would try what others mentioned: get two UT61E meters (quite decent resolution and features) and assemble your own 4-wire tester using one meter as ammeter, another as voltmeter and paired with a decent power supply.If you prefer to go at lower price, I would go for a pair of UT139C, UT136B/C or Mestek DM91A (slow continuity, though). Prices on these models fluctuate, though.