POLL: Multimeter default to AC or DC current? - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: January 10, 2012, 11:47:55 pm
content: There is a Twitter war going on with Fluke at the moment on this issue.They said:QuoteDave.

author: IanB
author_rank: Super Contributor
timestamp: January 10, 2012, 11:50:36 pm
content: Well, that's an eye opener. I never thought about the 87V being limited in that way. I'd like a meter to have separate dial positions for AC V, DC V and possibly DC mV.

author: EEVblog
author_rank: Unknown
timestamp: January 10, 2012, 11:54:31 pm
content: Quote from: IanB on January 10, 2012, 11:50:36 pmThis is only for current measurement where AC and DC both share the same switch position.Dave.

author: IanB
author_rank: Super Contributor
timestamp: January 10, 2012, 11:56:33 pm
content: Quote from: EEVblog on January 10, 2012, 11:54:31 pmOh, reading fail on my part. Never mind.

author: eternal_noob
author_rank: Regular Contributor
timestamp: January 11, 2012, 12:08:50 am
content: Defaulting to AC would be very unnatural for me, but for the guys who does the big chunky stuff will of course prefer defaulting to AC.

author: nukie
author_rank: Frequent Contributor
timestamp: January 11, 2012, 12:18:20 am
content: If they can save 50 or 60hz settings in eeprom why can't they save another parameter for AC / DC ? Is it hard to code a few lines to do that or is it the ASIC hardware that's not so flexible?

author: samgab
author_rank: Frequent Contributor
timestamp: January 11, 2012, 12:24:52 am
content: I usually work with DC current, so I find the way the 87V defaults to AC current really annoying. But I can see why it would be useful to some people.

author: Psi
author_rank: Super Contributor
timestamp: January 11, 2012, 12:27:29 am
content: Quote from: nukie on January 11, 2012, 12:18:20 amProgrammers time needed = 1%Managers time needing talking about the change and making flow/gaunt charts/presentations = 99%And the managers are probably payed twice as much.In all likeliness the programmers have already patched it and are waiting for everyone else to give the ok for release.Also they might want to redo health safety tests to cover their ass.

author: EEVblog
author_rank: Unknown
timestamp: January 11, 2012, 12:32:56 am
content: Quote from: nukie on January 11, 2012, 12:18:20 amThe new design uses an MSP430, so surely easy to do this?The ASIC is just for the input side stuff.Dave.

author: Unknown
author_rank: Unknown
timestamp: January 11, 2012, 12:38:26 am
content: I don't buy the argument that AC would be a preference for industrial use. In most cases a tong would be the instrument of choice for AC current measurement. Most of thecommon in circuit measurements would still be DC.The fact many of Flukes own Electrician or Industrial meters has no current range at all reinforces the theory.87 is an electronics meter, and probably falling victim of it's own success. Most 80 series used in industrial applications (I did say most, no egos under threat here) would never be pressed into service for much more than simple voltage, resistance and continuity readings, while a lesser meter would more than adequately performsuch tasks, the ruggedness, reliability and reputation of the 87 make them a must have for many professionals.

author: benemorius
author_rank: Regular Contributor
timestamp: January 11, 2012, 12:40:59 am
content: The real question (aside from the absence of a stored DC/AC setting) seems to me to be why are electricians using the same meter as we are? I'm all for multipurpose tools if they don't make compromises, but this is decidedly a compromise. Doesn't Fluke have a more suitable electricians meter? Are they not handling their marketing well enough? Or is the 87 really the go-to meter for everybody regardless of profession. If it is then it definitely needs to remember the last setting. Anything less would be criminal.

author: IanB
author_rank: Super Contributor
timestamp: January 11, 2012, 12:50:09 am
content: For me the current range of a meter is very rarely used, and if it is used it is normally for DC. I can't imagine measuring AC current in an industrial setting by putting the meter in the circuit. Wouldn't a clamp meter be far more common for that?

author: EEVblog
author_rank: Unknown
timestamp: January 11, 2012, 01:00:15 am
content: Quote from: benemorius on January 11, 2012, 12:40:59 amYes they do, that's the 110 series is for, and the 70/170 series too.The 80 series has always been primarily marketed as an "electronics" grade meter.You shouldn't buy an 87V if you want to do industrial electrical stuff, it's a more expensive lab type meter, you'd buy a 170 series instead.QuoteIt probably is the "go to" meter unfortunately, and that has fooled Fluke into thinking that the majority of users want AC as default.I'd love to actually see the survey Fluke used to get this info. I suspect they may have just derived it from some more generic general question instead of specifically asking "do you want AC or Dc default for current?"Dave.

author: EEVblog
author_rank: Unknown
timestamp: January 11, 2012, 01:01:38 am
content: Quote from: IanB on January 11, 2012, 12:50:09 amI believe it is, and I think that's where Fluke's thinking (and marketing research) is probably flawed.Dave.

author: EEVblog
author_rank: Unknown
timestamp: January 11, 2012, 01:08:00 am
content: Quote from: Uncle Vernon on January 11, 2012, 12:38:26 amI think you are almost certainly right, and the poll here is certainly reflecting that.This is an "electronics" forum, so most users would be basing their answer based on "electronics" (lab type, circuit board/project level) use. And it is clear that most prefer DC for an electronics meter, and I think that's a given.So the question is, who do Fluke want to market the 87 too? Electronics engineers, or industrial electricians?If it's the later, than that effectively forces the electronics people to move up to the top rung 280 series meter as their only option? (I can't recall if it defaults to AC or DC?) If so then that sucks, given the many other choices given to the industrial electricians and engineers, especially when most of them would likely use a clamp probe anyway!Dave.

author: alangarf
author_rank: Newbie
timestamp: January 11, 2012, 01:11:54 am
content: As I said in my Tweeter post for @eevblog and @flukecorp who would measure uA AC? Surely the more common use for a uA range is for small battery operated devices.I'd be happy if the setting wasn't stored in EEPROM and just lived in RAM. If it could just remember the setting while in use and switching between ranges. eg. switching to 'A', press the AC/DC button once. Use 10A input to verify the device under test isn't drawing more than 400mA to safe guard the mA input. Move device under test to the mA input when happy, then when you switch to 'uA' it remembers the setting and stays in DC mode instead of defaulting back to AC mode like it currently does. That is the most annoying thing. I should be able to set it once per session and have it remember that setting until it turns off.Alan.

author: samgab
author_rank: Frequent Contributor
timestamp: January 11, 2012, 01:34:36 am
content: Quote from: EEVblog on January 11, 2012, 01:08:00 am"While in a current measurement function, the"... 287/289 ..."meter will stay in the selected AC or DC current measurement mode when switching between A/mA and mA/µA. Whenever switched to one of the current measurement functions, the Meter will default to the last current type selected (AC or DC). "Also, pssh, marketing, don't get me started onmarketing... I think Fluke slipped up by deciding to go with AC current default on the 87V.It also bugs me how it switches back to AC each time the selector switch is changed between the A/mA and µA ranges.

author: Unknown
author_rank: Unknown
timestamp: January 11, 2012, 01:36:27 am
content: Quote from: EEVblog on January 11, 2012, 01:08:00 amThe reality is that most industrial use is actually crude electronic measurement in a rough environment or mains voltage or continuity measurement.QuoteI don't see the 80 series as anything other than an Electronics meter, the fact it is so popular in industry is more about what Fluke got wrong with the 28 rather than direction change for the 87. Logically the 28 would be the better instrument for top end industrial, but it is so far past the price point the 87 is the next logical choice.QuoteOnly if more changes are made that are detrimental to electronics lab use. The current default is plain dumb, but its not a game changer. Further dumb decisions could be.QuoteA lot of the so called industrial meters aren't, the rugged construction, the not too small size, make the 87 attractive to for use in this environment. The 110 series isn't as rugged, and many earlier models had serious deficiencies, HVAC meters with no capacitance, or DC mA current.I believe the industrial models need to be closer to the form factor of the 87 with more attention paid to mountings magnetic clips, test lead versatility, Mains Capacitor testing etc. Sub thousand dollar combo kits of rugged instruments would be the target for serious professionals.

author: kek
author_rank: Regular Contributor
timestamp: January 11, 2012, 02:04:18 am
content: My day job is industrial electrician and have checked AC current countless times but have never opened the circuit to do so. Always used a clamp on.I would rather have the meter default to DC so I could measure 4-20 mA DC, the only time I have ever opened the circuit to measure current,Ken

author: PetrosA
author_rank: Frequent Contributor
timestamp: January 11, 2012, 04:46:53 am
content: First off, I didn't take part in the poll so as not to skew the resultsI don't know the theory behind Fluke's marketing. I have never seen the 87V marketed as specifically for electronics/benchtop use. Grainger carries an 87V Industrial Meter Service Kit with an 87V, i400 clamp, test leads, alligator clips, thermocouple, etc. but that's very unusual. In fact, I've only ever seen ONE Fluke meter (an 87V) in ONE supply house between Lancaster and Philadelphia, PA. That's at least 10 supply houses over a 100 mile stretch. If you want Fluke around here, you have three choices - Grainger, Sears or a box store. What Fluke does on its displays at Grainger is market combo sets for HVAC or electricians so you could get a 117/322 in a kit ($305), or the industrial kit with a 179/322 ($340) or for HVAC the 116/322 ($305). Any of those kits will be cheaper than the 87V Industrial test kit ($461, approx. $125 less than buying separately). I suspect though that Fluke does a lot of its sales directly to buyers in large contracting firms - IOW, the electricians who use Flukes are getting them for free from work. If the Fluke rep can up-sell the buyers to 87Vs, they probably make a better commissionAn electrician who's using a DMM with clamp adapter most likely won't care what the A range outputs, since most clamps output AC mV.

author: Zero999
author_rank: Super Contributor
timestamp: January 13, 2012, 10:11:53 pm
content: I'd say neither, it'd be nice if the meter automatically selected the appropriate range and displayed +/- or AC depending on the voltage.

author: Unknown
author_rank: Unknown
timestamp: January 14, 2012, 07:15:40 am
content: Just like auto-ranging, this would definitely need a manual override. I can easily imagine situations where this would give the wrong value, like when trying to measure ripple voltage on a DC power supply. It also requires you to pay close attention to the indicators. Just set it to AC+DC if you want to measure both.

author: chrome
author_rank: Regular Contributor
timestamp: January 14, 2012, 10:17:31 am
content: It really depends on what you use it for, if it's an electronics meter then DCV if it's an industrial meter then obviously ACV.