Bench Power Supply Advice - Page 1
Forum section: electronics / testgear

author: moogle
author_rank: Newbie
timestamp: January 22, 2018, 11:30:59 am
content: Hi all,I'm looking for a decent bench power supply with the following specs:No overshoot + low noiseTriple output (dual ~30V, 3A and a fixed 5V supply)10mA/10mV or better resolutionlow fan noise, small size and programmable would be a bonus but not a primary factorIdeal budget is in the <~$200 - $300 USD range but I can spend more if it significantly increases the quality.I've so far narrowed it down to the following models:Instek GPE-3323GW Instek GPD-3303SSiglent SPD3303X-ESiglent SPD3303DSiglent SPD3303CDoes anyone have any experience/recommendations on how well these products perform in terms of overshoot and noise etc? Are there other supplies that would better fit my criteria or are cheaper?Any suggestions are appreciated, thanks!

author: eeviking
author_rank: Regular Contributor
timestamp: January 22, 2018, 06:06:57 pm
content: Anyone of those would work and should be decent quality.They are all very similar. I think the Siglents are just a copy of the GPD-3303S (at least the analog psu part)So you just need to find out if you want the spend the extra cash for the lcd display and added features.I have a Siglent SPD3303C, cheap, easy to use and works great.Fan is silent, but transformer on mine have some hum.The new GPD-3303S's may have overshoot on ch3. The old ones are fine. (you can tell the difference by the front terminal layout)

author: moogle
author_rank: Newbie
timestamp: January 23, 2018, 02:35:02 pm
content: That's good to hear about the similar design, I'll keep an eye out for a well priced second hand one. Thanks for your input!

author: kerouanton
author_rank: Regular Contributor
timestamp: May 28, 2018, 08:57:28 am
content: Hi,Same question here.I'm considering buying a Siglent SPD3303x to replace my old analog-vu meter EP603 PSU, but have a few questions :- are those banana plugs issues "solved"? Mainly the fact lead cables don't hold very well and tend to get out and not establish a good contact?- For a hobbyist, is there a reason to have a more expensive PSU as the SPD3303x, versus the SPD3303x-e that has a lower 10mV/10mA resolution? The price is much higher...- (or maybe there is a way to hack the xe to a x version?)

author: nctnico
author_rank: Super Contributor
timestamp: May 28, 2018, 10:22:42 am
content: It depends a bit on your requirements (programmable or not) but if you just need a power supply then you can also take a look at the GW Instek gpe-3323 . This has 1mA resolution on the current readback but it is much cheaper.

author: kerouanton
author_rank: Regular Contributor
timestamp: May 28, 2018, 12:48:18 pm
content: My idea is to buy a PSU that will last me for long as I don't buy often, thus fitting all future needs too. So yes it needs to be programmable, and with at least a timer.Now, I am split between different models and brands. As far as I understood the Siglent is good in terms of use, but has this banana plug issues (non-standard spacing between the leads, and non-standard holes that prevents a safe connection of the lead cables). I don't believe the first issue to be a problem for me, but the second may be more, thus my question.Price is indeed also in the balance, since I'm renewing nearly all my equipment (most are old). Getting all the stuff from Siglent may help me get a discount, too.

author: Mr. Scram
author_rank: Super Contributor
timestamp: May 28, 2018, 01:09:12 pm
content: One thing I overlooked when buying by bench power supplies was remote or four wire sensing. If you're looking for something accurate and programmable you may also be interesting in accurate voltage measurements at the source. In hindsight I probably would have looked for a model that has this capability.

author: BillB
author_rank: Unknown
timestamp: May 28, 2018, 01:12:29 pm
content: Quote from: kerouanton on May 28, 2018, 08:57:28 amI've got an SPD3303x-e and the plugs are fine. I think Siglent has corrected the issue on the current batch. The cost of the X over the X-E only makes sense for a hobbyist if he needs the 1 mV/mA resolution otherwise the X-E is more than adequate.And the C is much less and might be enough if you don't need/want the fancy display and timing.

author: MarkF
author_rank: Super Contributor
timestamp: May 28, 2018, 01:36:04 pm
content: Have they fixed the banana plug spacing on the Siglent? Dave's teardown noted that the spacing was not standard.

author: BillB
author_rank: Unknown
timestamp: May 28, 2018, 02:08:50 pm
content: Quote from: MarkF on May 28, 2018, 01:36:04 pmNo.

author: kerouanton
author_rank: Regular Contributor
timestamp: May 28, 2018, 06:04:32 pm
content: Thanks, that's much clearer for me.I'll probably go with the X-E

author: tautech
author_rank: Super Contributor
timestamp: May 28, 2018, 07:56:51 pm
content: Quote from: kerouanton on May 28, 2018, 06:04:32 pmI've had a good run with them and WRT the banana sockets, if you have only short stubby plugs of say 16mm they're too short to hold in properly. There's no standard for banana plugs but once you get to 18mm or longer they'll give no problems unless they are of poor quality.

author: kerouanton
author_rank: Regular Contributor
timestamp: May 28, 2018, 08:13:30 pm
content: I'm curious. What kind of applications would need a 1mA/1mV resolution PSU ?

author: tautech
author_rank: Super Contributor
timestamp: May 28, 2018, 08:42:38 pm
content: Quote from: kerouanton on May 28, 2018, 08:13:30 pmLow and micro power design and testing and in such you'd want much lower than 1mA.The X-E suits most buyers as if you need very accurate consumption measurement then a bench supply display isn't the right tool anyway. One of Siglents SDM meters could be added to give dual (V & A) and high accuracy measurement capability.

author: nctnico
author_rank: Super Contributor
timestamp: May 28, 2018, 08:54:52 pm
content: Quote from: kerouanton on May 28, 2018, 08:13:30 pmThink about battery powered or low power circuits which have low (sleep) currents you want to measure. Using a DMM isn't going to work because the current sensing resistance is too high and the wake-up current can cause an excessive drop in the power supply rail so testing can be difficult. I bought a Keysight E36313 specifically for this reason. It can measure low currents (below 20mA) with 10uA accuracy / 1uA resolution.

author: kerouanton
author_rank: Regular Contributor
timestamp: May 29, 2018, 05:08:08 am
content: That is clearer for me. And I guess the X-E will be enough for my needs. Thank you for your answers.

author: ziplock9000
author_rank: Regular Contributor
timestamp: May 29, 2018, 09:41:39 am
content: Does anyone know a cheap place to buy these in the UK? They seem more expensive than the prices noted here on eBay. Thx