best mA (hobbyist) multimeter with fast update speed? - Page 1
Forum section: electronics / beginners

author: exwhyzed
author_rank: Newbie
timestamp: March 09, 2015, 09:14:30 am
content: Hi all,After really going through the multimeters.xls file, watching the many helpful youtube videos of multimeter shootouts and buyers guides, I'm having a slight bit of difficulty choosing a multimeter that can measure mA, has a quick update speed, can do min/max, also has fast continuity speed, and is also cheapI need the min/max because i want to build balancing robots, and need to measure at what max mA/A the motors are at when i stall them. they will be operating at a stalled state the majority of the time in the robot, so its essential. I currently have a hard time trying to pinch the spinning motor while trying to look at the slow/choppy updating display on my cheapo multimeter.the Fluke 115 seems to be the perfect match, but it doesn't have an mA mode. This is sort of ok because i can interpret 0.006A as 6mA. the 115 also has min/max and fast continuity which is good. But its t's also pretty high priced. If i can't find anything else, i will most likely go with this one.the tekpower 4000zc seems fast at continuity and displaying results, is low priced, has milliamps and even microamps, and even the REL button, but no min/max, argh!Fluke 17B, cheap but no min/maxI don't need any true RMS or AC features, as i will just be measuring DC voltages and currents for my hobby projects.I looked at other Flukes, like the 77 and 87, and they seem just as expensive as the fluke 115. The Fluke product selector guide on the website did not help me at all.If anyone can recommend a fast updating multimeter, with the min/max function, quick continuity beeping, and also the ability to measure mA, i'll be grateful! In the meantime, I'll keep checking reviews and forums to see what i can come up with.

author: Seekonk
author_rank: Super Contributor
timestamp: March 09, 2015, 01:36:35 pm
content: This sounds like an ideal use for a UNO. Just using the debug screen would get you thousands of data points. On my solar power system I log battery slump for momentary loads that are over 100A. This gives me a general indication of connection and battery conditions. less than $10.I would seriously consider using a digital scope like Hantek 6022BE for $65. Trigger on the current and you will get a visual record that can be saved and current at each moment in time.

author: Sigmoid
author_rank: Frequent Contributor
timestamp: March 09, 2015, 02:58:57 pm
content: Well, since good multimeters are not too cheap, I'd buy them with flexibility and a long life expectancy in mind. You're not buying it for this project, but for all your projects over the next 10 years (or more, I've seen old HAM guys with multimeters older than their children). You can get a Fluke-87V at a reasonable price, if you keep your eyes open.The 87-V has a very reliable min/max feature. Most multimeters (and probably ALL cheap ones) implement min/max in software, which is completely inadequate for peak measurements. The 87-V has an analog peak hold circuitry. I have an 87-V, and a BK-Precision. The BK-Precision is a very good multimeter, highly reliable and overall a great buy at less than half the cost of the 87-V, but it can't do peak detect. You need peak detect for this project.

author: GreyWoolfe
author_rank: Unknown
timestamp: March 09, 2015, 05:17:25 pm
content: You haven't listed your country or price point but i found this on eBay:http://www.ebay.com/itm/FLUKE-87V-TRUE-RMS-MULTIMETER-WITH-LEADS-TESTED-/141597206719?pt=LH_DefaultDomain_0&hash=item20f7d9e8bfFlukes last for years and $189 USD shipped isn't bad. There is no make offer button but it wouldn't hurt to contact the seller to see if you can get a little more off the price.

author: Seekonk
author_rank: Super Contributor
timestamp: March 09, 2015, 06:35:52 pm
content: You will be quite lucky to get ten years out of a voltmeter today. Crappy LCD displays, look at all the Fluke repair kits for displays. Plastic just doesn't last.

author: exwhyzed
author_rank: Newbie
timestamp: March 09, 2015, 06:59:34 pm
content: Thanks for the info all! And Sigmoid and Greywoolfe, i think I will go for a used 87V.Seekonk, yes I've noticed that Fluke owners have been looking for ways of correcting fading displays, and have come across the lcd repair kits on ebay. Its something that i may have to look into sooner than later, when picking up a used fluke.Thanks once again!

author: mtdoc
author_rank: Super Contributor
timestamp: March 09, 2015, 07:14:59 pm
content: Look at the Brymen 257. At $135 fromforum member Franky's ebay store- it will cost you less than a used Fluke and do more. Later you can add data logging if you'd like by buying a $40 PC interface kit.I have both a Brymen 257 and Fluke 87V. Most of the time I reach for the Brymen, unless I need the extra resolution of the Fluke.Also there's a review of this meter in one of Daves Videos. He recommends it and you can often see him using it in his videos.

author: Rick Law
author_rank: Super Contributor
timestamp: March 09, 2015, 08:44:30 pm
content: Quote from: exwhyzed on March 09, 2015, 09:14:30 amExwhyzed,From the way you framed your post, just in case you did missed it:Did you also look into and understand something call the "burden voltage" and how it may affect your current?What you measured with a meter is with a drop due to burden voltage. Therefore, itmay not reflect what the current would be once the meter is removed from the circuit.Make sure you understand that part of the mix when you evaluate current.RickEdit:I re-read what I wrote. It was so awfully worded I felt compelled to reedit it (red is the edit).

author: PedroDaGr8
author_rank: Super Contributor
timestamp: March 09, 2015, 09:56:55 pm
content: What about the Brymen BM857S. Seems to fit your price range and gives a huge value for the meter. TME.eu lists it on their site (though not currently instock) at $125.10. The difference between the BM857A and the BM957S is that the S version has the upgrade safety components to meet the newest European safety regulations.

author: exwhyzed
author_rank: Newbie
timestamp: March 10, 2015, 01:55:17 am
content: Brymen's eh? I hadn't considered that brand/model before. I can see it has a button called "crest" which i'm assuming is another word for min/max or peak? the price also seems ok, but shipping to canada for any of these types of exotic meters really brings the price up.Rick Law, no i hadn't previously considered or have ever heard of burden voltage before. But i just looked it up online and now i'll have to take that into account when determining what a motor's stall current really is, thanks!So the two contenders for me are now the Fluke 87V and Brymen 257 (when it gets back in stock).

author: Lightages
author_rank: Unknown
timestamp: March 10, 2015, 04:01:44 am
content: Actually, you can get the BM257s for $135, including shipping to your door, from iloveelectronics on this forum. This is hardly expensive shipping. What can get you in Canada is the importation police wanting their taxes and import fees. Others have purchased Brymens from him, andwww.tme.eu, and they can share their experiences with you.

author: dannyf
author_rank: Super Contributor
timestamp: March 10, 2015, 11:18:28 am
content: QuoteUnless you are in some unique situations, burden voltage isn't a big concern.To minimized it, you can use hall effect sensors (for DC current) - they are usually not accurate and only for high current applications.Using a virtual ground approach would also minimize it -> they are however limited in range.