[time-nuts] Cooling Fan Information Needed

[gonzo .]

Hi Perrier,
I think I may have started that thread.

My first problem was that the side panels had been swapped so their was minimal airflow past the transformer.
Swapping the side panels dropped the heatsink temp by about 7°C

My second problem was that I couldn't source a 115V fan.  I replaced the fan with a  12V PAPST type: 8412/2.
These are a reasonably long life fan with similar characteristics to the original. It didn't add any additional cooling effect, but the drop in noise was appreciated.
My original fan was a Pamotor 8500D (also made by Papst). I assumed the long obsolete 8000D has similar specs to the current 8000DP

Although I havent fitted them yet, I also picked up a pair of 12V 40mm PAPST type: 412 F2H. These are to be fitted to the outside of the heatsink (recessed into the transistor channels) and I'll run them at ~7V.
Running slowly, they will be virtually silent, but I expect a significant drop in the heatsink temp.

cheers,
ian

http://img.ebmpapst.com/products/datasheets/DC-axial-fan-412F-ENG.pdf
http://datasheet.octopart.com/8412/2-EBM-Papst-datasheet-18371.pdf
http://www.ebmpapst.us/allpdfs/8000N.PDF



> Date: Thu, 23 Jun 2011 22:34:46 -0700 (PDT)
> From: Perry Sandeen <sandeenpa at yahoo.com>
> To: time-nuts at febo.com
> Subject: [time-nuts] Cooling Fan Information Needed
> Message-ID: <153279.85665.qm at web38006.mail.mud.yahoo.com>
> Content-Type: text/plain; charset=utf-8
> 
> List,
> 
> About a bazillion posts ago on the list (this translates to about two months) there was a discussion about cooling of very hot instruments such as the HP 5370A/B series.  
> 
> One poster related how he had replaced the stock OEM fans on a HP 5370 with ones used for cooling computers and achieving superior cooling with less noise, but gave no details.
> 
> As there are myriads of manufactures, CFM displacements, quality of construction and noise levels I?d appreciate some more information of what worked as well as what one might want to avoid.
> 
> Also I?d like to hear about any other experiences with improve cooling techniques.
> 
> Has anyone done case modifications such as adding fans to the top and/or bottom and how well it helped and if the remuneration was worth the aggravation?
> 
> Opinions welcomed.
> 
> Regards,
> 
> Perrier