Data logging with Siglent SDS814X - Page 1
Forum section: electronics / testgear

author: Bamphy
author_rank: Newbie
timestamp: March 27, 2025, 10:38:45 pm
content: I'm expecting my new scope tomorrow (Siglent SDS814x) and am looking for some tips. Any help or pointers would be much appreciated. I have never used a Siglent scope or any scope software before, but I'm going to give it a go!Here is some background.I'm trying to troubleshoot a problem at a remote location. I have a motor that spins at about 1000 rpm. There is an inductive pickup to monitor the RPM. This signal is fed into a software monitor and also through a resistor and capacitor to a very old school dial RPM Meter. The meterface has a mechanical stop and if the RPM drops the needle physically touches a contact, fires a relay, and kills the power to the system. The software also monitors the RPM and will shut it down if the RPM drops.The system has an intermittent problem where it shuts down every day or two and I can't figure out which part of the system is faulty. I don't know if the motor controller is failing and the motor is slowing down, or if the motor is spinning normally, but the signal is dropping out so that either the hardware or software monitor shuts it down. I would like to monitor the signal at a couple of points to make sure the amplitude remains good (30Vac) and that the frequency is stable.How can I set up my scope to take and store a measurement every 10 seconds or so? There is not a network connection at the remote site, but I can set up a PC there. Any help would be appreciated.Thanks in advance!Ben

author: egonotto
author_rank: Super Contributor
timestamp: March 27, 2025, 11:43:34 pm
content: Hello,perhaps the history mode will help.Another possibility would be to fetch data to the PC with SCPI commands. However, you would have to test whether 10 s can be reached.Best regardsegonotto

author: Bamphy
author_rank: Newbie
timestamp: March 28, 2025, 01:15:41 pm
content: Thanks for the ideas. I'm excited to play around a bit.Ben

author: tautech
author_rank: Super Contributor
timestamp: March 28, 2025, 07:59:34 pm
content: Using a DSO for these types of tasks and its capturing ability along with trigger capabilities can seem daunting to the new DSO owner but it's really quite straightforward.Break down the test subject into the signals that will tell you what's going on.Pick the one that you think will give you the best/first indication of a fault and determine what that signal is doing when the fault eventuates.Set the tigger to that channel and assign the appropriate edge, rising of falling.Assign an appropriate trigger level for the normal run/good state.Select Single triggering at an appropriate timebase, where you then decide if you need to see pre-trigger or post-trigger info the most and adjust the H Pos of the trigger accordingly.Connect other channel test points as necessary paying particular attention not to introduce ground loops from where probe reference leads are connected to the DUT.When set correctly, you can leave the scope to monitor the DUT and for the SDS800X HD with a LAN connection and NTP time correctly set, the single shot capture will have a timestamp when the fault happened.If a LAN connection is available, WiFi is possible with certain devices, access to the DSO remotely is also possible from afar where the capture can be downloaded or saved locally to the scope and/or you can easily set the DSO to Single again to be ready to capture another fault.

author: TomKatt
author_rank: Frequent Contributor
timestamp: March 28, 2025, 11:29:03 pm
content: I upgraded from an SDS1104X-E to a SDS804X HD. The older SDS1104X-E had a data logging option that was perfect for that kind of application. Despite the many improvements the new scope brings, I was disappointed to learn that the new SDS804X HD no longer includes that ability and comments I've read from others with more knowledge on the subject seem to indicate that it's not likely to be added in the future. A strip chart type analysis is a great way to troubleshoot problems like you describe - especially for slower transitioning failures that go beyond what can be captured in a single shot trigger.Still - the suggestion offered by tautech sounds like an excellent strategy.

author: KungFuJosh
author_rank: Super Contributor
timestamp: March 28, 2025, 11:58:21 pm
content: It should be possible to setup TestController on a local computer to log data for you. If the signal is live from the scope to TestController, you could log anywhere from every 0.01s to 10s or a custom interval.You can also use the remote web view to control the scope from the computer. You might be able to setup a screen recording software to monitor that and get your timestamps from TestController to see what's on the scope screen.

author: tautech
author_rank: Super Contributor
timestamp: March 29, 2025, 12:51:33 am
content: Quote from: TomKatt on March 28, 2025, 11:29:03 pmAnd that's the thing, with an instrument that offers all the modern DSO does, deciding how to best use it is one thing but taking a step back and looking at the DUT, which in this case is a system is also just as important.For all we know there is some digital control affected by too much ripple on Vdd, enough to impact on device thresholds.As those that have a good amount of repair experience would say; first check power supply rails.