Siglent SPD3303C Review and Questions - Page 1
Forum section: electronics / testgear

author: Roger Need
author_rank: Regular Contributor
timestamp: March 06, 2023, 12:44:20 am
content: I just received a Siglent SPD3303C linear power supply that I ordered on Amazon. Tested it with various loads yesterday and pleased with performance. It met all specs and observed the folllowing:Interface is intuitive and save/recall easy to do.Rotary knob encoder was smooth and can be rotated quickly with minimal lagNo overshoot on load/noload. Rise time in millisecondsRMS noise was under 1 mV RMSOCP was implemented in firmware and worked wellAt low currents fan noise was very low and only slight transformer humRotary encoder knob has pushbutton capability but it does not appear to be used according to manual. Anyone found out how to use the pushbutton feature? If I push it in and power on only the digit 5 appears on the display. I wonder what that does?My unit was older stock with a cal date of June 2022 and latest firmware for Version 1.From firmware release notes a Version 2 of the hardware was released in September 2022.Does anyone know what the changes are in V2 and if it affects performance or user options? I still have 30 days to return if V2 is a better product.Thanks - Roger

author: abeyer
author_rank: Frequent Contributor
timestamp: March 06, 2023, 01:32:40 am
content: Quote from: Roger Need on March 06, 2023, 12:44:20 amI'm pretty sure that's how you turn it up to 11.

author: tautech
author_rank: Super Contributor
timestamp: March 06, 2023, 02:02:40 am
content: Quote from: Roger Need on March 06, 2023, 12:44:20 amAFAIK this HW revision is just part of normal HW development/improvement as is SPD3303X/X-E had a similar HW upgrade recently too.I suspect the 2 are related however Siglent does not share the details of HW changes only flagging them in firmware versions if SW need be changed to support the changes.If there are changes a user might notice, they are reflected in datasheets and user manuals.

author: 7thSenpai
author_rank: Contributor
timestamp: December 27, 2023, 05:20:37 pm
content: Only thing I found the push button does is resets the overload condition. That is when the led display reads O.L.

author: MathWizard
author_rank: Super Contributor
timestamp: April 23, 2025, 09:48:37 pm
content: Older thread I know, but how do these compare to the SDP3303X-E ? I have the latter, and would like a 2nd PSU for more channels. It would take a lot of time, effort and/or money, to make a PSU with a nice case, and good buttons/etc, so for now, I should get another 1.I think 2 3303X-E's can be hooked up together, what about with the 3303C models ? And how have they held up over the years, do they still make them new? Or when did they stop ?I should have a look at Rigol and a few other PSU's too. I'd get a used 3303X-E if I could, so I'm trying to go down in price, not up. The new Siglent 4CH PSU's like nice, but yeah I don't want to spend that much for my hobby usage.

author: tautech
author_rank: Super Contributor
timestamp: April 23, 2025, 11:34:00 pm
content: Quote from: MathWizard on April 23, 2025, 09:48:37 pmLatest X-E have an updated display that more clearly show Series or Parallel modes.Dunno about C models but X-E models can certainly be placed in Series mode then multiple units in series for elevated voltages up to the max Case to Terminal ≥ 20MΩ (DC 500V) datasheet rating.

author: MathWizard
author_rank: Super Contributor
timestamp: April 24, 2025, 02:25:47 am
content: Well I looked at some used PSU's on ebay, and I decided to go with some thing less digital, way cheaper, and way more repairable and mod-able, by me. So I ordered a working, INSTEK PC-3030, it's a CV-CC 2x30V and a 5V channel. It looks about the same form factor as the Siglent 3303xx, and has about the same features. So that should be perfect, and it's nice to have something with meters again. I can always try adding some digital display, and controls if I want, it's a good way to learn more programming.

author: electr_peter
author_rank: Unknown
timestamp: June 02, 2025, 07:27:34 pm
content: Is FW 1.02.01.02.03 suitable for SPD3303C HW version V1.0? FW 1.02.01.02.02 required HW V2.0 revision, but it is not clear with this one. Link to FW:spd3303c-series

author: tautech
author_rank: Super Contributor
timestamp: June 02, 2025, 09:29:00 pm
content: Quote from: electr_peter on June 02, 2025, 07:27:34 pmStudy the release notes here and all should be clear:https://int.siglent.com/download/firmwares/?ProId=43

author: electr_peter
author_rank: Unknown
timestamp: June 03, 2025, 05:58:56 pm
content: Quote from: tautech on June 02, 2025, 09:29:00 pmLinks to specific firmwares have more comments than the latest version release notes, now it's clear. SPD3303C with earlier HW(<2.0) can be upgraded up to 1.02.01.01.03R10.

author: electr_peter
author_rank: Unknown
timestamp: June 03, 2025, 06:05:33 pm
content: Few notes on EasyPowerX - it works, but is a very limiting. There is too little feedback from PSU about actual output status and set values. Commands send over USBTMC (SCPI) are not 100% reliable, front panel can be also changed while in remote mode - more feedback is needed about command execution status in SW.Below are few points on how EasyPowerX SW can be improved with little effort. I am not sure how to reach Siglent on EasyPowerX matters.There should be a button "get PSU status" which loads set V/I values from PSU to PC and readback PSU output state.Slider is not suitable for output On/Off function (due to feedback issue). EasyPowerX should use 2 separate clickable buttons "On"/"Off" and not a slider.Additional colored box "Output" should indicate On/Off status based on readback.independent/series/parallel selection sometimes fails to change PSU state with no indication on SW (too fast click with mouse - relays on PSU doesn't respond). "1 out of 3 circle" selection should be changed to 3 buttons with additional indication with color based on readback status.There is a live output V/I display, but set values are a mystery as they are not read back from PSU (SCPI command is available). You can set V/I values, but can't see what is set. There should be additional line of set V/I values (based on readback) below current value display (again, needs "get PSU status" button).It would be nice to read/set 5 memory values from SW.