HP 6632A Power Supply Fan Silencing

[compgeke]

Recently I picked up an HP 6632A quite cheaply, under $75 shipped. The thing works great with the slight exception of the fan being loud.
(see 1st image)

Being as I plan on using this on my desk, I wanted to quiet it down but I don't want to have it over heat from throwing some low power low noise fan in that barely moves 12 CFM. After some searching around I found there are some fans with built in thermal couples for adjusting their speed without outside control but they aren't particularly easy to find for 60mm. That's where this board I found on amazon comes in. It's a stand alone fan controller, it takes 12V input (just what the 6632A uses) and can control 1-3 fans via PWM adjusting speed based on the temp it senses on its thermal couple.

The installation went pretty easy, I skektchily mounted it with a bolt and some insulation to an existing hole in the chassis and wired it all up. I have the board jumpers set for 40% minimum fan speed, ramp up past that at 35*C and hit 100% at 45*C. From testing with jumpers initially set for 40*C, it'll keep it right at 40 (see the last image). With jumpers set to 35 it'll keep it around 36 as per the Fluke 52 (last calibrated in '95, take it with a grain of salt).

See the pictures for the installation. I assume if anyone else wants to do this you'll be able to figure it out on your own, if not you shouldn't be opening this up.

And for more pics, http://imgur.com/a/vgK5E . The forum threw a "Maximum 2000KB blah blah" when trying to add them all. It's like I'm living in 2004 again.

[mtdoc]

After some searching around I found there are some fans with built in thermal couples for adjusting their speed without outside control but they aren't particularly easy to find for 60mm.

This Vantec 60mm temp controlled fan works great. I've used it on 2 retrofits now, including a HP 6632A.  It's quiet and can move plenty of air if things get hot enough.  That board you're using looks like a reasonable solution as well.

[Micke]

After seeing HighVoltage´s hint in this thread https://www.eevblog.com/forum/testgear/agilent-34410a-noisy-fan/msg486137/#msg486137 I bought a couple of these high quality 60mm PAPST 612MI fans with integrated speed controller: http://www.ebay.com/itm/162257691307?ul_noapp=true
Despite auction say only shipping to Germany, it was no problem buying living outside Germany.
I planned to put this in my loud Agilent E3645A PSU, however I noticed you must connect a small dummy resistor in parallel with the fan to increase the power consumption a little, since the PSU monitors the current and beeps and gives an error message if the current is too low. Quite handy, the original connector on the fan fits the PSU (but the polarity is reversed though, so removing the sockets and reversing them was needed...)