ESR in DMM - Page 1
Forum section: electronics / general

author: andrewkirkby
author_rank: Contributor
timestamp: May 26, 2013, 12:26:50 am
content: Hello Forum!Does anyone know of a DMM that has ESR functionality? It seems to be a very handy function for repair and maintenance testing and would be really great to have in a multimeter.. I'm looking at buying the ESR meter peak makes (link below) in the UK as I'm doing more and more PSU diagnosis but before spending some notes I wanted to see if anyone knew of anything on the market?I'm not looking to spend massive amounts as I already have a Fluke 289 which I won't be replacing any time soon but if there's anything anyone knows of or even an adaptor style box like dave's uCurrent it'd be much appreciated!Hope we're all well!Andrewhttp://www.peakelec.co.uk/acatalog/jz_esr60.html

author: Unknown
author_rank: Unknown
timestamp: May 26, 2013, 12:33:24 am
content: None that I'm aware of, definitely none of the name brands. Good ESR measurements requires proper LCR meter functionality (an AC test signal for starters), and DMM's usually don't generate AC signals. Capacitance functions are also crude and inferior compared to LCR meters. A DMM is just not the right tool for those jobs.An adapter could be made by replacing the LCD by a DAC, but the device wouldn't be much simpler or cheaper than a stand-alone meter, and less versatile.

author: andrewkirkby
author_rank: Contributor
timestamp: May 26, 2013, 12:39:00 am
content: That make more sense.. Excuse the slightly green nature of the question..! I guess adding a signal generator of any form is a bit beyond the scope of average meter design.What are peoples thoughts on that peak device? I have one of their Atlas DCA75 pro testers which is great although I'd love it to have a backlight! I'm not really sure how well they sell outside the UK but based on my experiences with the DCA it's probably pretty well designed.I guess an LCR meter would be a more accurate approach but I wouldn't have the first clue how to use it.. i guess that was the case with my scope too but with help from Dave and others on here I've learnt a lot..Thanks for the advice..!

author: kripton2035
author_rank: Super Contributor
timestamp: May 26, 2013, 07:54:53 am
content: you can build this :http://kripton2035.free.fr/analog%20esr/esr-lowohm-silic.htmland output the result to your dmmalso this one from PA4TIM eevblog forum member :http://kripton2035.free.fr/analog%20esr/esr-pa4tim.html

author: andrewkirkby
author_rank: Contributor
timestamp: May 26, 2013, 11:29:35 pm
content: Like it! Thanks..

author: Unknown
author_rank: Unknown
timestamp: May 26, 2013, 11:35:14 pm
content: For decent LCR meters (eg. the various Agilent and IET instruments, but also some cheaper Chinese LCR meters that have been discussed on this forum), ESR, sometimes called Rs, is a standard feature. It's just a matter of hooking it up and selecting the correct function.I haven't used the Peak Atlas devices. From what Irecallreading, the functionality was OK. Main downsides were odd case design and crappy leads.

author: G7PSK
author_rank: Super Contributor
timestamp: May 27, 2013, 08:22:32 am
content: I have a Peak ESR 60, It is very easy to use you just clip it onto the capacitor to be tested and press the on button it does the rest and reads out the capacitance and the esr at the same time, it does not do very small capacitors but those are not normally used in smps in a position where esr is of importance.

author: andrewkirkby
author_rank: Contributor
timestamp: May 27, 2013, 01:07:11 pm
content: Yeah the Peak DCA 75 I have is alright, as you said the case is a bit awkward (more for storage) although i found the leads on mine to be pretty good. Also, the USB function on the DCA Pro is fantastic.. Gives you proper graphs of component analysis. Also they ditched that 12V battery for an AAA. Still, the case is plasticy and the buttons are a little un-solid. Wouldn't survive too long in anything but a hard case.If they did a version of their ESR meter with the same USB functionality I'd be delighted. I think I'll maybe bag one of their ESR devices though.I might have a crack at building that DMM add on though. Looks like a bit of a project to keep me amused.While we're on the topic of filter caps, what are people using for discharge? I'm making a bleed resistor but wondered if anyone knew of 'the best' instructions for those? I have various 5W resistors and a neon which I was thinking about putting into one of those mains voltage detection screwdrivers but wondered if anyone had any instructables links?..Thanks for all the help, this place just became my favourite spare time site..!

author: G7PSK
author_rank: Super Contributor
timestamp: May 27, 2013, 05:49:27 pm
content: The Peak ESR 60 discharges the capacitor before testing it automatically. If it is a really big one I just use a test lead.

author: andrewkirkby
author_rank: Contributor
timestamp: May 27, 2013, 10:46:29 pm
content: Is it ok with mains levels?

author: tom66
author_rank: Super Contributor
timestamp: May 27, 2013, 10:54:25 pm
content: Only for small capacitors, below 22µF I think. Above that it is required that you discharge them. I think the limit is 30V for any size cap, up to 450V for 22µF and below.

author: andrewkirkby
author_rank: Contributor
timestamp: May 28, 2013, 12:55:52 am
content: Thought that might be the case. I work on power amps a lot where 10,000 uF isn't uncommon and there can be a hell of a lot of them in Pro Audio kit.Time to hunt out a 5W resistor and a pair of old probes! What do we rekon a good discharge resistance value is? I've seen varying opinions on this. I'll be looking to discharge 240V minimum over a few seconds..I think I'll order a peak ESR + I am semi tempted by that agilent LCR meter with ESR functionality though. He did a teardown of it comparing the new vs old model.Damn it Dave, why do I have to buy everything you make a video of..!!

author: G7PSK
author_rank: Super Contributor
timestamp: May 28, 2013, 03:26:14 pm
content: The abuse voltage for the Peak ers60 is 275 volt for <10uf and 50 volt for >10uf but it will test to 22,000uf but go no lower than 1uf.

author: andrewkirkby
author_rank: Contributor
timestamp: May 28, 2013, 06:52:20 pm
content: Yeah, the audio psu caps I'm working with are 10,000uF at 63V bit of a smack in anyone's money.

author: don.r
author_rank: Frequent Contributor
timestamp: May 30, 2013, 02:08:08 pm
content: For low-end ESR, this one seems to be the winner:https://www.eevblog.com/forum/testgear/new-esr-meter-mesr-100-v2-by-'jingyan'No idea what maximum rated capacitance is, however. It appears to be an improvement from the esr-60/70.

author: andrewkirkby
author_rank: Contributor
timestamp: June 07, 2013, 10:43:58 am
content: Incase anyone was loosing sleep, I bottled it and bought an Agilent U1733C.. I think I might have some sort of psychological issue where I must have shiny kit.. Still, it's probably far more useful in the long run and should be more accurate than the other options..