Power supply - Active or Passive cooling

Hi,

I was wondering what would be a better option for my new printer.
A power supply with a active (built-in fan) or a passive cooling (perforated sheet) ?

Peter

I have only got the active type, exactly the same as in your photograph, so can't compare the two.

The fan cuts in and out during operation. It is not on all the time. Only disadvantage I can think of is the fan noise if you want a super quiet environment. Maybe the passive cooling type is a bit cheaper to manufacture?

For the same capacity passive PSU's are more expensive to manufacture, at least traditionaly. With that being said, newer designs of psu's are cutting this down as the efficiency of switching power supplies increases the power wasted decreases therefore the thermal needs are lowered. At the same time I have seen very cheap power supplies faild because of cooling when they were designed to be passive.

I used a 1300w server PSU for my build because it was free to me and high quality at the same time. I am looking to add a 150W+ heater to my build for the chamber fairly soon so extra overhead is nice. The PSU regulation is very good holding 12.3V all the time. The only thing I wish I could do is ramp the voltage to 13.5-14v.

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I use a 300W passively cooled PSU similar to the one in your photo, and I've been very happy with it. I enjoy the silence when the machine isn't printing.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Passive will be more reliable if its thermal design is sufficient, because there's one less moving part to fail and fans have short life spans, cheap ones doubly so. But a good passively cooled supply is likely to cost more (larger heatsinks required) than a fan forced one of the same rated power.

A cheap passive supply is likely to have under-specified heatsinks, but might work really well if you give it gentle external airflow; best of both worlds, ie should run cool by default and should not die when your external fan fails.

It seems that lower-power supplies are more readily available as passive so you might have good results using multiple smaller supplies, e.g. one for each heater and one for steppers + logic.

Edited 1 time(s). Last edit at 10/16/2014 01:26AM by polyglot.

Buy a passive one with vents and activlely cool it. I have had very good luck with passive graphics cards and a slight airflow. Passively cooled parts are overbuilt, and a slight breeze can keep them well below the maximum recomended operating temp.

I have only observed what you call a "passive" cooling power supply used inside an enclosure that managed airflow through the case. Never seen one being used out in the open.....

I have the power-supply-active, the fan only turns on when it starts to get a load (IE heating the heatbed), so its very quite when not using it.

Edited 1 time(s). Last edit at 05/07/2015 05:56PM by mikes3ds.

Quote
mikes3ds
I have the power-supply-active, the fan only turns on when it starts to get a load (IE heating the heatbed), so its very quite when not using it.

These are sometimes called "semi-passive". You get the advantages of a lower maximum internal temperature of actively cooled power supplies and the lower noise of passive (fanless) power supplies.