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Products => Test Equipment => Topic started by: delmadord on July 15, 2017, 07:41:39 pm

Title: Silent bench PSU
Post by: delmadord on July 15, 2017, 07:41:39 pm
Hello,
I know this question has been asked here a zillion times, but still. I am currently using MATRIX MPS-6003D (from tme.eu) and it works reasonably well for my tinkering (did not test the ripple or overshoot yet, need to find a tutorial for doing it in a proper way), but the fan is really loud and on all the time and it is ridiculous.

Things that I do care about the most:


I was thinking about the U8001A but then I found that it is not really a silent one, as stated in this review (https://www.eevblog.com/forum/testgear/review-teardown-agilent-u8001a-30v-3a-linear-power-supply/).

Can you please suggest me something? Thank you.
Title: Re: Silent bench PSU
Post by: tautech on July 15, 2017, 07:58:30 pm
The Siglent SPD3303X or X-E is very quiet at low current levels and meets your criteria except for form factor.
http://www.siglenteu.com/pdxx.aspx?id=1116&T=2&tid=17 (http://www.siglenteu.com/pdxx.aspx?id=1116&T=2&tid=17)
Title: Re: Silent bench PSU
Post by: jpb on July 15, 2017, 09:12:11 pm
I have a TTi PL320QMD which is totally silent (no fan) and is linear so very low noise but it is physically quite large.

With Bench PSU there are trades-off.
If you want low electrical noise then this indicates a linear supply but then it is less efficient so produces more heat so either needs a fan or needs to be large to supply enough heat sinking.
Combining switched mode with linear is electrically noisier but more efficient so can be smaller.

The TTi EL series are fan-free,("Silent fan-less convection cooling") e.g. :
https://www.rapidonline.com/aim-tti-el303r-30v-3a-90w-single-output-psu-85-2197 (https://www.rapidonline.com/aim-tti-el303r-30v-3a-90w-single-output-psu-85-2197)

It meets most of your criteria except for the flat physical design for which the Keysight supplies might be better (though more expensive).

Note also that the EL series lacks sense terminals (to compensate for cable voltage drop) whilst the more expensive TTi supplies do have this.
Title: Re: Silent bench PSU
Post by: alm on July 16, 2017, 02:20:34 am
Since noise is not a factor, I would search for a switching power supply with either no fan or good fan speed control. And pray they do not have excessive coil whine :P.

Plenty of linear power supplies are passively cooled, but they will be large and will often be deep and narrow rather than short and wide. Front panel space is usually more of a premium than depth. Especially for rack-mounted applications. A passively cooled linear power supply that can supply 90 W will likely exceed your unstated maximum dimensions.

For higher power levels, passive cooling (large mass of metal) is more expensive than sticking in a high-speed fan, so expect to pay more (e.g. from TTI) than the cheap Chinese power supplies that will use a minimal heat sink and fan.
Title: Re: Silent bench PSU
Post by: nctnico on July 16, 2017, 02:40:03 pm
Gophertc http://www.gophertc.com/ (http://www.gophertc.com/) makes cheap and flat power supplies. However from the teardowns I've seen and my general experience with cheap switching lab power supplies I would hesitate to buy one.
Title: Re: Silent bench PSU
Post by: BBBbbb on July 16, 2017, 07:56:53 pm
Gophertc http://www.gophertc.com/ (http://www.gophertc.com/) makes cheap and flat power supplies. However from the teardowns I've seen and my general experience with cheap switching lab power supplies I would hesitate to buy one.
Gopher(t) is OK, they live up to their specs, at least those popular small flat versions.
I've got a cps3205 (32V-5A), and I've been using it for carry around, as it is quite small, and been driving some motorized bed's motors with 3-5A on several occasions (150-200kg) w/o any problems. No heating issue as well.
Title: Re: Silent bench PSU
Post by: delmadord on July 17, 2017, 08:32:19 am
Hello,
thank you for some nice tips on the topic. If no other suggestions come, I will probably go with the Sigilent one.

Title: Re: Silent bench PSU
Post by: tautech on July 17, 2017, 09:12:19 am
Hello,
thank you for some nice tips on the topic. If no other suggestions come, I will probably go with the Sigilent one.
Defpom put the X-E through some tests:
https://www.youtube.com/watch?v=MwSO9cu5c1o (https://www.youtube.com/watch?v=MwSO9cu5c1o)

Note, the X-E has only 10 mV, 10 mA resolution.
Title: Re: Silent bench PSU
Post by: nctnico on July 17, 2017, 09:56:18 am
If you go for that formfactor (approx 16cm high) then the GW Instek GPE-2323 may be a cheaper alternative. It has 1mV/1mA resolution and individual volt/current controls for the main channels but no remote programming or any other fancy features.
Title: Re: Silent bench PSU
Post by: nidlaX on July 17, 2017, 10:03:26 am
I don't know about the GW Instek model, but I own the Siglent SPD-3303D and it is indeed a very quiet power supply with an aggressively down-throttling fan profile.
Title: Re: Silent bench PSU
Post by: FrankBuss on July 17, 2017, 10:12:44 am
I can confirm this, the SPD3303D is very quiet, and the support is helpful when you have a problem, see my review (https://www.eevblog.com/forum/testgear/siglent-spd3303d-review/). Works very well.

If you don't want to spend that much money, I can recommend this:

http://cgi.ebay.de/322554113030 (http://cgi.ebay.de/322554113030)

There are multiple resellers for the same power supply. I bought one many years ago which looked exactly the same, and I still use it sometimes. It has no fan, but it is not exactly flat. I guess a linear power supply (and you don't want a switching power supply for your lab gear) can't get too flat, if it doesn't have a fan.
Title: Re: Silent bench PSU
Post by: anotherlin on July 17, 2017, 02:57:37 pm
You may want to try HP/Agilent/Keysight E361x series of PSU.
They are very simple a few knobs, with digital readout, and no fan! Big passive radiator in the back.
They can be found on ebay.
Title: Re: Silent bench PSU
Post by: nctnico on July 17, 2017, 03:58:56 pm
You may want to try HP/Agilent/Keysight E361x series of PSU.
They are very simple a few knobs, with digital readout, and no fan! Big passive radiator in the back.
They can be found on ebay.
I second that suggestion although they don't have accurate readouts and IIRC no adjustable current limit.
Edit: I had a different PSU in mind. HP made so many different ones.
Title: Re: Silent bench PSU
Post by: rdl on July 17, 2017, 04:54:21 pm
A pair of E3610A handled all my power supply needs for years. There are a variety of models in this line. The E3610A/11A/12A do have adjustable current limiting and differ only in maximum output voltage. Their meters use 7107 A/D converters and the resolution is limited to 0.01 for amps and volts, at least for the E3610A model.

These are pretty good power supplies, but not perfect, and are no longer made, so would have to be purchased used. I would avoid the earlier HP versions as there were some issues which were fixed later. Probably any new enough to have the red/black/green binding posts instead of the red/red/black will be okay.
Title: Re: Silent bench PSU
Post by: nctnico on July 17, 2017, 05:29:21 pm
I have a Keysight E36312A to play with for a couple of days. The fan only comes on when necessary (nearly full load) but it never gets really loud. Pretty much similar to a modern oscilloscope. Ofcourse the Keysight E36312A is way more expensive than the other PSUs mentioned so far but I think the very accurate readouts for both voltage and current (including low current range) add a lot of value. You don't need extra DMMs to measure the voltage current. OTOH it can do 25V/2A max with the two 25V channels in parallel or 50V/1A with the two 25V channels in series.
Title: Re: Silent bench PSU
Post by: dom0 on July 17, 2017, 08:21:35 pm
30 V / 3 A is really not a big issue passively (switched or controlled taps) and has been available since the 90s for little money (e.g. ps-303 series around 100 EUR—not the best design, but often good enough).