Need to advice/help on Keysight U1272A & FLuke 289 - Page 1
Forum section: electronics / beginners

author: Platforms
author_rank: Newbie
timestamp: July 20, 2017, 12:05:40 pm
content: OK. currently I need to buy a multi-meter, and these 2 basically are in my mind.Question 1. They keep claiming that you can measure Amperage at the same time while you are measuring voltage.How can they make this happen? From my understanding, if you don't run the meter serial with the wire, you can't get the amp number at all....Question 2. Do Fluke 289 have that Smart Ohm function? Or offset compensating like the U1272A?Do Fluke 289 be able to calculate the wire length at the low 50Ohm range?Question 3. For the nS mode, what is the lowest & highest resolution which Fluke 289 can go up to?Question 4. For the software, anyone know any alternatives to use this function without buying the Fluke unit? Basically this is one of the biggest killer for me. I can't believe the unit & software is like 250$, 1/3 of the meter price. on the other hand, Keysight only want 40$. and free software. Very reasonable.For those of you who own either one, how do you like them?Specially the Fluke guys, do the 289 chew batteries like no tomorrow or you can still get some reasonable battery time? And let say if you are @ Ohm mode and "accidentally" poke a 600V outlet. what message will the fluke shows?

author: mahi
author_rank: Regular Contributor
timestamp: July 20, 2017, 03:29:25 pm
content: Quote from: Platforms on July 20, 2017, 12:05:40 pmWho's claiming that? Some meters, like Dave's upcoming 121GW, support power measurement (simultaneous measurement of voltage and current) but the Fluke 289 definitely does not. Fluke does not advertise that anywhere. I'm not familiar with the Keysight U1272A but since the datasheet nowhere mentions this feature it's quite safe to assume it does not either.QuoteNo. At least not that I know of.QuoteYou mean relative (delta) mode? Yes.QuoteNo. No multimeter would be able to do this unless it "magically" knows the wire gauge and resistivity.QuoteIt measures up to 50 nS with a 0.01 nS resolution.QuoteThe Fluke 289 is supported in Sigrok and LabVIEW. You'd still need the adapter cable although you can build your own for much less than Fluke is charging.QuoteThe Fluke 289 is probably my favorite meter but it's not without its flaws: It's slow to start up (~8 seconds), could use a higher contrast display, the menu system is not always intuitive, you can't view the trend while logging, it's fairly bulky and it suffers from a leaking supercap issue (see below). Then again it makes up for a lot of that with excellent accuracy and some clever features.QuoteBattery life is stated as 100 hours. That's about 1/3th of the U1272A. I never found it much of an issue. Note that the 289 is plagued by aleaking supercap issuewhich dramatically reduces battery life. I think most of the horrid battery life reports are due to that issue. Fluke changed the supercap for a rechargeable battery in the current version which supposedly fixes the issue. If you have/get an older one you can have it serviced by Fluke or (if you don't care about warranty) replace the supercap yourself.QuoteI have no idea what would be displayed but the millivolt, ohm, diode and capacitance ranges are protected up to 1000 V.

author: RoadRunner
author_rank: Frequent Contributor
timestamp: July 20, 2017, 04:07:24 pm
content: Quote from: Platforms on July 20, 2017, 12:05:40 pmI own U1272A and i have used fluke 289 at place of work. 289 is more focused on logging , it is a big heavy thing , i feel U1272A is more focus on normal use , you can do logging though. It is lighter than fluke 289 .buying software is pain. so i have written python scripts to get data out of the FLUKE 289,here is the document i refered to.www.labviewpro.net/upfiles/remote_spec28X.doc

author: Platforms
author_rank: Newbie
timestamp: July 23, 2017, 06:57:51 am
content: Quote from: mahi on July 20, 2017, 03:29:25 pmYea, that's 1 thing which I keep researching. 1 side, seems like some meter can do that, but on the other hand, it just completely reverse the theory why there is clamp meter for today.Basically same as Gossen Metrawatt Metrahit Energy multimeter, they claim that too, but when I call their tech support, he basically said that I need to buy a adapter to install it in-between the unit. (From my understanding, same as before, must be serial)For Dave's 121GW meter, do you know where can I get some more info of the spec?QuoteWhat is the different in-between Ohm & nS mode anyways? From what I understand, Ohm apply low voltage to do the measurement already. It's not like Insulation meter, apply high voltage to test resistance......QuoteLike what kind of clever features does it have? Any specific function which basically save your life or save you a ton of time to do the troubleshoot? (I keep looking thru the menu from fluke online, but I only find out a bunch of basic manuals.....)

author: Platforms
author_rank: Newbie
timestamp: July 23, 2017, 07:12:35 am
content: Quote from: Gaurav on July 20, 2017, 04:07:24 pmThat's what I figure out from how they promote their meters too, but so far, how can you remember all those functions on the u1272a? ex. if you need to use 1 of those functions, and you forgot how to pull that out, usually how you solve it? so far, I can see this meter have lots of functions, but..... setting them up seems to get quite complex. not as simple as fluke....How buggy is the firmware on this unit anyways? Personally I like the U1272A more, but in Canada, almost no one heard of it...... and most of the review online on this meter is like 3year plus.... kind of outdated.....

author: Platforms
author_rank: Newbie
timestamp: July 23, 2017, 07:51:50 am
content: Quote from: blueskull on July 20, 2017, 04:32:26 pmHV testing.... you mean High Voltage or.....For my situation, I own a T5-1000, and a Megger MIT 420. Currently I need something which can measure electronics (something more accurate than my T5), logging function is good, but I only need like 10min max (so I know Fluke 289 is completely overkill) what more important for the logging part is how many time per sec.(I work in a food processing plant, so lots of heaters, steam cookers, motors, and electronics to control valves)Currently I have a few meters in my mind.Keysight U1272APro: Lots of features, "Sounds" WAY more refine than a F87V, have even more functions than F289, but can be gimmick stuffCons: Seems super buggy, and not too much support in CanadaCurrently, still waiting for them to answer me that do their 4-20mA function. Can it source or simulate.....Fluke 289Pro: Fluke stable, and problem freeCons: seems less function or less may be less gimmick than U1272a. Price is quite hi, almost not worth that priceFluke 87VPro: Fluke stable, and problem freeCons: really outdated in my opinion.Fluke 279 (The one with thermal camera)Pro: Fluke stable, can record those video or imagesCons: thermal camera not as good as flir DM284, measure part seems to be worst than F87Vstill waiting for Fluke tech support to give me the spec of the meterGossen Metrawatt Metrahit Energy multimeterPro: German quality, and basically I have an energy meterCons: not too much detail or support in Canada (Even worst than Keysight) and *just find out you need to hook it serial to the unit to do the energy measurement ( can be wrong since lack info on this unit)Flir DM284Pro: Very good thermal image part. Meter have most of the function which I want.Cons: meter part made by extech. quality may be not too great. Their tech support don't like to pick up the phone to reply back.Currently still getting more detail on the unitDave's 112GW (still no idea what to expect from this unit)Hoping that it have those sweet function of a Keysight 1272A & Gossen Metrawatt Metrahit Energy multimeterWho got more detail on this unit, please let me know

author: alm
author_rank: Super Contributor
timestamp: July 23, 2017, 08:10:43 am
content: Quote from: Platforms on July 23, 2017, 06:57:51 amThe test voltage is the same low voltage, but 0.01 nS resolution is equivalent to 0.1 TOhm (of course accuracy will not be amazing and noise may be a problem). That is much higher than you would be able to measure in Ohms mode. So it is basically a high resistance mode. Resistance mode from 1 mOhm to 500 MOhm, conductance from 20 MOhm to 0.1 TOhm. Neither would be suitable as insulation test, since that would have to be performed at much higher voltages.

author: mahi
author_rank: Regular Contributor
timestamp: July 23, 2017, 09:25:27 am
content: Quote from: Platforms on July 23, 2017, 06:57:51 amClamp meters simply use a different technology to measure current - it has nothing to do with a meter's ability to measure "power". Most multimeters use a shunt resistor to measure current. Clamp meters on the other hand measure the magnetic field induced by the current in the wire. The major advantage of clamp meters is that they allowcontact-lesscurrent measurementswithout interrupting the circuit. That's much safer than a shunt resistors in a high energy environment. The disadvantage of clamp meters is lower accuracy - especially at lower currents.Power measurement requires a multimeter that can do simultaneous voltage and current measurements (whether that's from a shunt resistor or a current clamp is irrelevant).QuoteThe 121GW is still in pre-production phase. As far as I know no final specs, nor user manual has been released yet. However, fellow board member joeqsmith received a pre-production model from Dave for some early impressions/testing (note the multimeter was uncalibrated with unfinished/buggy firmware). He made a video about power measurements you may want to check out (link).Basically the meter is put in series with the load to measure current, but at the same time a third lead is used to measure the voltage over the load.QuoteThe nS mode on the Fluke 289 is just to measure extremely high resistances. You should not confuse this with an insulation tester which is used to detect insulation breakdown at (typically) high voltages. Compare it to measuring the resistance of your body with a regular multimeter and holding a probe in each hand. You will read very high resistance. This may lead you to the misunderstanding that your body is a quite decent electrical insulator (see threadWhy'd i get shocked by wall outlet?). Higher voltages can break down the insulation of your skin. That does not make the multimeter's readings wrong - they are just not applicable for when you'd touch mains voltage...QuoteIt's not like these features are not found on other meters, especially the higher-end models you are looking at, but they are implemented very well in the Fluke 289. Some of the things I like:Min-Max mode: Naturally min-max mode is not unique to the Fluke 289 but the large graphical display allows the current, maximum, average and minimum values to be displayed all on a single screen instead of having to toggle between each of them. Even better is that the minimum and maximum values have timestamps.Inverse continuity mode: Usually continuity mode is used as short circuit detection (beeps when the measured resistance is below a certain threshold). The 289, however, has a mode to detect open circuit. In other words, it beeps only when the circuit goes open. This is great to find cold/bad solder joints, bad contact in wiring,... (the U1272A can do this as well I noticed after reading the user manual)Relative measurement in %: Great to test tolerances.Trend logging: Obviously you can do trend logging with any multimeter that has PC connectivity but I like being able to log and view data without having to set up a computer next to it. I guess this will get less and less relevant with more and more meters supporting Bluetooth and compact smartphones replacing laptops for this purpose. However that still requires the smartphone to stay near the meter (Bluetooth range). A self-contained meter like the 289 can just log on its own.I had a quick look at the U1272A manual and it too has some nice features I wish the 289 had: Auto-diode test (the older Fluke 760 series had it, so why can't the current flagship do it?) and especially scale transfers (I really miss this on the 289 when using current clamps).QuoteThe shortest interval is 1 sample per second but it can detect and record events within the interval (so glitches can be detected and logged even though they may not have occurred exactly at the interval).

author: mahi
author_rank: Regular Contributor
timestamp: July 23, 2017, 09:36:54 am
content: Quote from: Platforms on July 23, 2017, 07:51:50 amJust download theuser's manualand take a look at chapter 5.7. There are diagrams in that chapter showing the various ways to measure power with the Metrahit Energy.