Rigol DM3068 Issues, Remarks, Improvements requests - Page 1
Forum section: electronics / testgear

author: KedasProbe
author_rank: Frequent Contributor
timestamp: February 09, 2014, 02:27:52 pm
content: I wrote down some notes about problems with this DMM to make a quick video of it but since I keep postponing it and people may want to know it rather sooner than later. Here the subject list of the not existing video.Maybe I will still make the video but until then here is the subject list:Issues1) 100PLC boot problem, screen freeze.(change PLC during frozen screen and reboot)2) 512k readings memory isn't present/useable, should be according to specifications. (it's only 5000 samples)3) .csv file: number of significant digits is only 6 should be at least 7. (.xdat format stores double format, see my file converter .net program)4) AC+DC for DC measurement, Max. voltage must be within 125% (+25%) of range at all times to get a correct DC value.5) Sensor curve: program does not send the table. Max 1 sample/s (only USB)No software except driver, SCPI, Webpage6) Webpage doesn't work (anymore) ? (commands are ok reading doesn’t work)7) Rigol Command set doesn’t support all functions you need to change command sets.(and the Agilent command set doesn’t support all functions either, you need both)8 ) Screen off, isn't off it shows, text 'screen is off'9) My cooling fan seem to sit a bit lose since it makes a silent rattling noise sometimes.10) 10kS/s not enough process resources left for buttons and screen, result: screen freeze and non-responsive.(Remotely this wouldn't be a problem)11) ‘Power on’ must be set to ‘last’, since also in this Rigol device they saved the number format in the 'last’ settings (should have been present in the same memory that stores the language)12) No way to just download the current memory to PC (with SCPI), it need to be started from SCPI. (store to USB first)13) Supply fuse need to be changed for 230Vac to lower value. (although 230V was set correctly)Remarks & Improvementsa) Second function only frequency, some DM3058(E) screenshots are shown on DM3068 pages. (The DM3058 has second measurement)b) AC -3dB on 2.1Mhz (2V range) much more than Agilent 34461A, 300kHz still measures a relative accurate value.c) The frequency as second measurement cannot be stored.d) Brymen 0.015% more DC (0.02% vs 0.002% 2V Range)e) Calibration sheet gives no values of the calibration.f) Show noise graph measured with short 100PLC 10PLCg) Reset of trend curve, should stay like histogram.h) Show time since start measurement and store end time in csv/xdat file. (unit: ms)(or add time stamp for every measurement)i) Current source diode test, 0.997mA and 99.7µA etc.j) The Webcontrol code isn't signed with a certificate so you have to add the IP number in the exception site list of java.EDIT added j)

author: iDevice
author_rank: Regular Contributor
timestamp: February 09, 2014, 03:23:32 pm
content: Quote from: KedasProbe on February 09, 2014, 02:27:52 pmTrue, but not very annoying as not or hardly ever used I guess.QuoteYep, at first I thought they just made a typo in their literature, they maybe meant 512K of sample memory or something.But even then, 100 bytes per sample seems unlikely.That said, if they wanted to say 512kbits, then it begins to make sense.QuoteThis one is actually the usual locale problem with java programmers who hard-code their dot and comma separators, instead to ask the API for the current locale.Try to set your local to US english and it'll work.I've reported this Bug to Rigol a few month ago, but there was no new release since, so let's hope it will be for the next one.QuoteMine is whisper quiet, it's actually the quietest fan of all my Rigol gears.QuoteThis made me regret to have chosen the 3068, the last digit is kind of useless anyway as this DMM is so noisy that you can't make any use of it, so better go for the added functionality of the 3058.Frankly, I don't understand why the 3068 has less functionality that the 3058, except for the trending.QuoteThis has been added in the latest firmware. The voltage is also increased so that you can now test leds.

author: KedasProbe
author_rank: Frequent Contributor
timestamp: February 16, 2014, 11:53:54 am
content: Quote from: iDevice on February 09, 2014, 03:23:32 pmI noticed that you could set it to US English and customize/change all settings back to your own country and it will still work. Not the other way around. (Editing your own country to the 'right' settings doesn't work)

author: iDevice
author_rank: Regular Contributor
timestamp: February 16, 2014, 01:40:36 pm
content: Quote from: KedasProbe on February 16, 2014, 11:53:54 amYep, this is my default setting as well since years now because like I said, this problem is widespread as many developers think the whole world use English notation.

author: KedasProbe
author_rank: Frequent Contributor
timestamp: February 16, 2014, 01:58:51 pm
content: Yes, I know thanks for the info, what I wanted to add is more clear in this picture (this setting works)I also tried to determine the internal (and .xdat) storage resolution, seems to be 11.5 Digit:(each value in the left column represents the difference between 2 measurements)