RS PRO DMM, the IDM505, 100,000 counts, 0.015% DC V accuracy... - Page 1
Forum section: electronics / testgear

author: samgab
author_rank: Frequent Contributor
timestamp: February 04, 2017, 02:30:01 pm
content: Has anyone seen or used, or own this meter?The RS Pro IDM 505 or APPA 505?http://nz.rs-online.com/web/p/digital-multimeters/1241960/As per the subject headline, it has 100,000 counts, and 0.015% basic DC V Accuracy.Also has data logging, Dual display, Auto hold, True RMS, Auto backlight, and a few other nifty looking features.It looks pretty good, but I'd like to see inside it and get some real world experiences of others with it.I'm on the lookout at the moment for an affordable and reasonably good DMM with 60,000 counts or higher.I'm keeping an eye on the progress of the 121GW Dave Jones special, but this meter caught my eye too, and it looks like it might have potential, if the build quality and real world use measure up to how it looks on paper (screen).

author: samgab
author_rank: Frequent Contributor
timestamp: February 04, 2017, 02:41:58 pm
content: Meh, looks like it's this - at least five years old - APPA 505 rebranded:

author: rstofer
author_rank: Super Contributor
timestamp: February 04, 2017, 06:21:59 pm
content: I think I would spend some time with a spreadsheet calculating accuracy (including digits) versus something similarly priced. I don't know how it would come out but the fact that the "best" DC accuracy involves +-0.015% plus 20 digits and AC accuracy is +-0.4% plus 50 digits seems to jump out at me. Then there is the question of what "best" DC accuracy means. Or, more to the point, what would "worst" mean? If I have to throw away 20 counts, I might as well ignore the LSD and, if that's the case, it is only a 10,000 count meter. I shouldn't say that (it probably isn't technically correct) because I haven't done the comparison against another meter but it is a lot of digits to ignore.http://nz.rs-online.com/web/p/digital-multimeters/1241960/

author: samgab
author_rank: Frequent Contributor
timestamp: February 04, 2017, 07:03:37 pm
content: Yeah, I've kind of lost interest in this DMM. Too many unknown factors, it's not a trusted brand. I'm thinking a Keysight U1282A will be a better option. Twice the price, of course...The resolution is more important than absolute accuracy to me, which is why I'm really after at least 50,000 counts.Anyone have any suggestions for a really good 50,000 or 60,000 count dmm with data logging, excellent input protection and build quality, and a reasonable/low price?

author: Lightages
author_rank: Unknown
timestamp: February 04, 2017, 07:20:32 pm
content: Not the counts you want, but rather 10,000/6,000 count, 0.06% best basic accuracy, 87,000 records at up to 20 per second, CATIV / 1000V UL listed to latest IEC standards, $185 USDplus shipping.http://www.tme.eu/en/details/bm525/portable-digital-multimeters/brymen/bm525s/USB adapter is another $44 USDor if you can live with data logging on on a PC, 50,000/500,000 count, 0.02% basic accuracy, CATIV / 1000V, $216 USD plus shipping:http://www.tme.eu/en/details/bm869/portable-digital-multimeters/brymen/bm869s/Perhaps you cn find them for close to the same price in NZ but I doubt it.

author: iainwhite
author_rank: Unknown
timestamp: February 04, 2017, 07:25:59 pm
content: Another option may be an "old-stock" Keysight U1252B from ebay... 200USD offer plus 40ish for shipping to NZSeveral forum members (including me) have bought them. Of course there is some risk compared to a new purchase.Thread discussing itHEREEdit: correct model number

author: samgab
author_rank: Frequent Contributor
timestamp: February 04, 2017, 07:40:50 pm
content: Quote from: iainwhite on February 04, 2017, 07:25:59 pmExcellent thanks; this might be the droid I'm looking for... The U1252B is still a good meter, and a lot of the improvements from that to the U1282A aren't things I'd need anyway, like I don't need it to be waterproof... Cheers!Edit after some checking in the datasheet: Hmmm, 36 hours battery life? I know it's rechargeable, but still. Black/white LCD screen and that's the battery life? Bit of a shocker.

author: samgab
author_rank: Frequent Contributor
timestamp: February 04, 2017, 08:16:28 pm
content: Quote from: Lightages on February 04, 2017, 07:20:32 pmThanks, yeah logging to a PC was what I had in mind anyway. I was interested in the Brymen but wasn't sure of a good supplier of them to NZ, but I'll do a bit more digging as I'm interested in that model. I really need minimum 50K counts. (I already have an 87V for taking readings of up to 6K counts, but it doesn't have data logging (to PC), and in certain uses with Li-ion cells I need the resolution of at least 50K counts, for the extra order of magnitude resolution over the 87V.)I thought the new old stock U1252B would be the one, but I'm really put off by that 36 hour battery life. That would drive me nuts, sometimes single sessions of logging take several days or more.So I'll either wait for Dave's new meter, or bite the bullet and get the U1282A (800 hr battery life and takes AA cells!), or try to find a good supplier to NZ for the Brymen BM869...

author: iainwhite
author_rank: Unknown
timestamp: February 04, 2017, 08:35:24 pm
content: Quote from: samgab on February 04, 2017, 08:16:28 pmSorry the idea didn't work out.I'm looking forward to Dave's 121GW meter too!Good luck anyway.

author: Wytnucls
author_rank: Super Contributor
timestamp: February 05, 2017, 04:10:14 am
content: Had another look at the Keysight datasheet.Power consumption is higher than most current meters, with a battery life of only 70 hours with a 9V alkaline battery.Worse still, 30 hours with the rechargeable Ni-MH (3 1/2 hours charge time)The U1251B should do better, with about 100 hours, at 105mVA instead of 165mVA for the U1252B.

author: samgab
author_rank: Frequent Contributor
timestamp: February 05, 2017, 05:33:42 am
content: It's annoying that most DMMs with rechargeable batteries and charging solutions recharge via the ports, so you cant use them for logging and charging at the same time. I understand there are interference and isolation issues with a precision DMM, but it's still annoying. It would be useful to keep the DMM plugged in while doing logging over longer periods of time. But I guess that's why there are bench meters.

author: Daruosha
author_rank: Regular Contributor
timestamp: February 05, 2017, 07:26:55 am
content: I have the DMM (APPA 505) and I had the same accuracy vs resolution concerns. So tried to cross check the readings against my DM3068 and boy, the APPA was spot on!The input protection is very very good as well, both fuses are big HRC types and the whole construction and build quality is stunning. (it's not a fluke 289, but not far from fluke products). Continuity check is super fast and clear too.The data logging works quite well and i have done several data gathering projects with the dmm, however it doesn't support trigger mode data logging ( for example you can't auto-hold a reading and automatically save it to the memory)The only weak spot is the gimmicky software (took me a week to figure out the proper driver for Windows 10), and firmware update, or calibration documents! There's no documented procedure of callibration or any support for future firmwares. Still not a huge deal for me, but for some people it might be a serious deal breaker. Fortunately i didn't find any bugs yet (fw version 2.15) and after 3 years the meter accuracy looks exactly as same as the first day. Very happy with it.All and all, i love this DMM and i'll buy a second one very soon.

author: Daruosha
author_rank: Regular Contributor
timestamp: February 05, 2017, 07:46:58 am
content: If you want to take a look at inside, check out teardown videos at below:https://youtu.be/U09XeXBwlg0

author: samgab
author_rank: Frequent Contributor
timestamp: February 05, 2017, 02:19:08 pm
content: Quote from: Daruosha on February 05, 2017, 07:46:58 amThanks for this video. It set my mind at ease with regard to some of the concerns I had about its internal build quality and safety/protection measures. It looks well designed and has adequate safety measures designed in to meet its claimed CAT rating. I saw 4 x PTC's, 3 MOV's, and on the other side there are some large surface mount power resistors, so that's all good. The jacks look to be good quality and solid and, as you mentioned, both fuses are the large BUSS HRC type, plus there are isolation slots cut in the PCB in the appropriate places. The designers appear to have known what they were doing and not built it down to a price.Tell me please, is it really 100,000 counts? The info page says 100,000/10,000 counts, and I figured it was 100,000 counts on the main reading, and 10,000 counts on the second reading of the display. Is that correct? Thank you.EDIT: Never mind, I had a closer look and I see that the bar graph goes up to 10, so you'll get 4 decimal places up to 9.9999V, then 3 decimal places up to 99.999V and so on, presumably.

author: Daruosha
author_rank: Regular Contributor
timestamp: February 05, 2017, 02:27:11 pm
content: It has two modes (regular 10,000 counts and hi-res 100,000 counts) .It slows down a little bit on the hi-res mode (readings/second), but not much. On the secondary display it's always 10,000 counts still.I would like to remind you again about the lack of proper calibration/adjustment docs (deapite mine is well within specs after a few years) and firmware updates too. Not an issue for me (considering its price range).I'm in the process of sniffing its serial communication protocol and develop a rather handy logging software for it.Happy measuring :-)

author: samgab
author_rank: Frequent Contributor
timestamp: February 05, 2017, 02:51:15 pm
content: Quote from: Daruosha on February 05, 2017, 02:27:11 pmThanks for your info, it's helping... I'm tending towards the Brymen 869S now, because it's 50,000 counts in normal/fast mode, and 500,000 counts in high res/slow mode, and the price is good. I've emailed tme.eu asking for a quote for that meter and the USB connection kit, and I believe it will work out even better priced -after shipping and taxes- than the APPA 505 sourced locally. I don't believe the Brymen comes with calibration info either, whereas the Keysight U1282A does come with cal papers.

author: Daruosha
author_rank: Regular Contributor
timestamp: February 06, 2017, 01:39:11 pm
content: I have nothing against the Brymen (in fact i love to buy one. I'm a multimeter addict), just keep in mind the basic DC accuracy of brymen is %0.02 vs %0.015 of appa (better resolution vs more accuracy in another word).Also the maximum current resolution on Appa 505 is 0.1micro amp vs 0.01 micro amp on Brymen.The overall build quality of Appa is still way better than the Brymen too.

author: samgab
author_rank: Frequent Contributor
timestamp: February 06, 2017, 06:27:45 pm
content: Thanks for the advice. They're both fine meters, no doubt. I think the only solution is to get both, but I can't afford that, sadly.The Appa 505 though is ±(0.015%+20d) whereas the Brymen is ±(0.02%+2d). The 20digits is the more critical number there to my way of thinking. I haven't had hands on with either of them yet, so I can't speak to the build quality, but I haven't seen any of the owners of the Brymen BM869S say its build quality is lacking in any major way; to the contrary, they all seem to rave about the high level of build quality, and having seen its innards, I believe it has all of the appropriate protections in place to meet its claimed CAT IV 1kV, EN61010-1, and for ESD, the EN61326-1 standards.The APPA 505 seems to be rated to CAT IV 600V, EN61010-1, and also meets EN61326-1 for ESD protection.On the other hand, the 505 comes with the USB cable as standard, whereas it's a cost-added optional extra with the Brymen.On the OTHER other hand, when I include the cost of the USB cable in with the Brymen, plus shipping from tme.eu to NZ, it still works out as a lower cost option than the APPA bought locally.Then again (ran out of hands), the APPA has Auto hold, and runs on 4x AA cells which is preferable to me than the Brymen's 9V battery.The APPA refreshes 6x/sec at 10,000 counts compared to the Brymen's 5x/sec at 50,000 counts.It's all nit-picking though, they're both more meter than I really NEED...Having said that, I'll probably go for the lower spec'd BM867S (ONLY ±(0.03%+2d!!!)), because I can live without the temp data logging, although it would be useful, and sometimes resolution is more important than all-out accuracy, which is often the case with me, working with li-ion and NiMH cells and batteries. The (relatively, and only very slightly) lower accuracy rating of the 867 is still very good accuracy, as good as my Fluke 87V in most ranges, and it has the same high resolution as the 869. The VFD stuff I wouldn't use. And it's cheaper by a significant margin, bringing it under the price cutoff for not having to pay import duties and tax when shipping it to me in NZ, and tme.eu replied to my email saying they won't give any discount on the 869. It's rare for me to pay list price for an item like this!I've learned a lot from these posts. I found that there are about 4 or 5 manufacturers who make the exact same meter as the Brymen 867 and 869 just rebranded and with slightly different cases, but the same under the skin. And there are about 4 or 5 brands that do the exact same meter as the APPA 505, just rebranded and with different colours. In both groups, all of the different meters within that type are all identical in terms of internal construction, specs, and functions.I think maybe I should just wait for the elusive Dave DMM to come out to compare that one, then make a choice. I'm not that fussed about the bluetooth connectivity, but the high voltage LED test, the low burden voltage, and a few other features have me interested in it. It would be nice to just get all three kinds, but the budget doesn't stretch that far unfortunately.

author: coromonadalix
author_rank: Super Contributor
timestamp: July 23, 2017, 04:23:49 am
content: there was ; IDEAL Electrical 61-498 490 Series Digital Multimeters/0.015% DCV Accuracy/100,000 Count LCD Display