Do you often use peak/hold feature on your benchtop DMM? - Page 1
Forum section: electronics / testgear

author: LinuxHata
author_rank: Frequent Contributor
timestamp: July 16, 2022, 08:55:54 pm
content: Hello.I'm developing an "upgrade" kit for Keithley 179 display module, which will have modern OLED indicator, with higher brightness and customizable colors.It will be "plug-n-play" module, no modification to DMM needed, you just unplug old display module and install the new one.Since there will be separate MCU on that board, which will eliminate these flashing zeros on over range, and replace them with non-flashing "-----", I can implement some additional features:1. Peak value display - the screen will split into two parts, and larger digits will show the current measured value, and smaller digits will show the peak value measured.2. Freeze/Hold display - Again, screen will split into two parts, and larger digits will show the current measured value, but smaller digits will hold the value, which was actual, when that button was pressed.3. Continuity beeper - Activated by separate button, and when measured value is below or over certain value (user adjustable), there will be loud buzz.How do you think, are these features interesting to anyone? (Personally, I don't need first two, but need the 3rd one)

author: AVGresponding
author_rank: Super Contributor
timestamp: July 16, 2022, 10:18:32 pm
content: Peak, only rarely, hold fairly frequently, continuity, all the time. But when you need them, youneedthem.

author: tautech
author_rank: Super Contributor
timestamp: July 16, 2022, 11:03:10 pm
content: Yep, if you're not using Hold then it's probably a low energy, low density or low voltage DUT.For most everything else you need both eyes on what you're doing rather than short something out, blow the ends from probes etc where instead Hold in invaluable, just invaluable.

author: tooki
author_rank: Super Contributor
timestamp: July 17, 2022, 10:52:22 pm
content: I use peak occasionally and continuity all the time. However, the reason for using those features is that they’re far, far faster than the display update speed. A continuity tester that only responds in 400ms (the 179’s conversion time) is completely useless, and I don’t mean that as hyperbole: I’d never use it because even a $10 meter with horrible continuity will be better. Similarly, when I use my Fluke 87V’s peak detect, it’s because of its ability to detect 1ms pulses, which is far, far far, faster than the meter’s display update rate. Both of these are features implemented deep in the meter’s hardware and software, so you can’t emulate them by screen scraping a meter with a very slow display.So while I applaud your inventiveness at wanting to expand the feature set, I don’t think it’d actually add much in the way ofactualutility because the performance would just be too poor.

author: LinuxHata
author_rank: Frequent Contributor
timestamp: July 20, 2022, 08:15:36 pm
content: Well these are a good points to consider (peak & hold), and I never thought about them, since I'm used to use digital scope, when I need to detect pulses 1ms and shorter. Regarding the continuity, yes, this won't be terribly fast, but as said, it will have customizable trigger ranges, have no idea if this feature is implemented in any of current DMMs - this means, you can set that say, beep will only sound, when resistance is in between, say 1k and 1.2k. This feature is quite usable when you need to test and sort and debug many similarly wired components or wires - sound will be only heard when the measured value is in range, so you can save time by not looking on the display.So, saying shortly, I will not implement peak and hold features, but will do adjustable continuity beeper.

author: tooki
author_rank: Super Contributor
timestamp: July 21, 2022, 04:48:36 am
content: Some bench DMMs (like my Keithley 2015) have adjustable continuity thresholds, but not a resistance window like you’re indicating. However, some might have that as a form of configurable pass/fail testing.

author: Hydron
author_rank: Super Contributor
timestamp: July 21, 2022, 01:45:30 pm
content: If you have a DMM6500 then you can write a script/app to do whatever custom behaviour you want it to (an auto-hold app is actually one of the examples supplied by Keithley). It should be noted though that unfortunately apps can still be a bit buggy, especially trying to exit them and go back to normal meter operation.This works because the app/script has access to the full rate measurements coming from the meter, rather than needing to wait for each display refresh. I agree with tooki that continuity based on the full conversion time would be pretty useless.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: July 22, 2022, 06:39:36 pm
content: QuoteWhat good is the hold button if you have to let go of one of your probes to push the button? I would rather have a function that would chirp whenever the display registers a change in the reading. Then I would know to look up at the meter. Unless I am not understanding the operation of the hold button.

author: tautech
author_rank: Super Contributor
timestamp: July 22, 2022, 08:35:10 pm
content: Quote from: BILLPOD on July 22, 2022, 06:39:36 pmHold mode for Siglent bench meters provides a list of the last 10 IIRC measurements, and each when taken you are notified with a beep.Just the perfect functionality for when you’re probing in amongst HV and need keep your eyes on what you’re doing.Screenshot added

author: tooki
author_rank: Super Contributor
timestamp: July 23, 2022, 01:11:27 pm
content: Quote from: BILLPOD on July 22, 2022, 06:39:36 pmI think they implicitly meant auto-hold. Though I do think I’ve seen some old meters with a hold pushbutton right on the probe itself.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: July 23, 2022, 01:44:07 pm
content: Yes, after my remark about the hold button, I went to Google and found 'AUTO-HOLD', and learned how it works by watching videos. I then found that one of my meters actually has it, (EEVBLOG 121GW). More reason to love that meter. I then went to the meter's manual and found a description of it. I always RTFMs but sometimes they need to be re-read from time to time. Now I'm on the search through my other meters to see if any others have Auto-Hold.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: July 24, 2022, 01:28:17 pm
content: Whelp.....I went through all of my meters and the only other one that has auto-hold is my Fluke 189, (most of the others have a plain ol' hold button). And it works better than on the 121GW in that the read appears instantaneously, whereas the 121GW hesitates for what seems like 2 or 3 seconds, which is not acceptable in some instances.Also, I see a hold button on my 26 year old Keithley 2000, and I'm guessing there is some convoluted method of making it 'auto', but its going to take a lot of RTFM to figure that out.

author: bson
author_rank: Unknown
timestamp: July 25, 2022, 07:37:27 pm
content: Peak no, hold yes.Especially hold with a table view. Makes it easy to verify the values of say a dozen resistors. I can measure them all and then check the table to verify they're all say 100Ω. It's rare, but it seems once a year or so I find an SMD part has found itself into the wrong values, or even Mouser shipped me the wrong value (happened once). Frustrating to track down on an assembled board, so I make a habit to double check all passives before placing and reflowing. (Unless they have a value printed of course, but that's mainly the larger parts.)