Author Topic: HP 6632A fan replacement and front panel posts  (Read 11579 times)

0 Members and 1 Guest are viewing this topic.

Offline mtdocTopic starter

  • Super Contributor
  • ***
  • Posts: 3575
  • Country: us
HP 6632A fan replacement and front panel posts
« on: June 11, 2013, 07:07:51 pm »
In my newbieness I'm putting together a lab and got a HP 6632A powersupply/load from fleabay a while back. As others have noted the fans are loud.  So I replaced it with THIS temperature controlled fan for $10 on newegg.

Quiet now! Even when drawing full power the fan is barely audible.  My lab bench is in a walkout basement utility room where the ambient temp is usually in the mid 60s F - so I doubt this fan will ever need to crank up to full speed.

I also put in some front side binding posts which turned out to be pretty easy to do. There were premade holes in the plastic on the back side of the front panel with output tabs avaiable on the PCB next to them. All I had to do was drill through the metal front plate.  Used 12 awg silicon wire for the connection.



 

Offline Dave

  • Super Contributor
  • ***
  • Posts: 1356
  • Country: si
  • I like to measure things.
Re: HP 6632A fan replacement and front panel posts
« Reply #1 on: June 11, 2013, 07:54:09 pm »
I suggest you grab your air compressor and go berserk on that heatsink with a duster attachment. I cleaned my 6632B (bought off eBay) that way, and you wouldn't believe how much fine dust came out the other side.
<fellbuendel> it's arduino, you're not supposed to know anything about what you're doing
<fellbuendel> if you knew, you wouldn't be using it
 

Offline mtdocTopic starter

  • Super Contributor
  • ***
  • Posts: 3575
  • Country: us
Re: HP 6632A fan replacement and front panel posts
« Reply #2 on: June 11, 2013, 11:47:18 pm »
I suggest you grab your air compressor and go berserk on that heatsink with a duster attachment. I cleaned my 6632B (bought off eBay) that way, and you wouldn't believe how much fine dust came out the other side.

Thanks. I already did that.  Yes, lots of "cough, cough" dust....
 

Offline bingo600

  • Super Contributor
  • ***
  • Posts: 2050
  • Country: dk
Re: HP 6632A fan replacement and front panel posts
« Reply #3 on: June 12, 2013, 11:45:33 am »
Where did you get the front posts from ?

They look HP alike  :-+

/Bingo

Who just discovered that those fan's can't be bought in EU
Meaning i have to get them for $10 + $10 in shipping from US.

And the stupid DK customs rules says i have to get the two i need in two different shipments ($12 goods value limit), else i have to pay $35 in VAT on top.

 

Offline mtdocTopic starter

  • Super Contributor
  • ***
  • Posts: 3575
  • Country: us
Re: HP 6632A fan replacement and front panel posts
« Reply #4 on: June 12, 2013, 06:16:09 pm »
Where did you get the front posts from ?

They look HP alike  :-+


Radio Shack LINK -Who'd a thunk ?  :wtf:
 

Offline grenert

  • Frequent Contributor
  • **
  • Posts: 449
Re: HP 6632A fan replacement and front panel posts
« Reply #5 on: June 16, 2013, 01:30:21 pm »
I've been favorably impressed with those Radio Shack binding posts.  They seem to be really durable, without brittleness, and as said, they mimic the original HP ones very closeley.  Interestingly, I noticed that some packages of these plugs are made in the UK!!  Wonder who the OEM is?
 

Offline Andy Watson

  • Super Contributor
  • ***
  • Posts: 2142
Re: HP 6632A fan replacement and front panel posts
« Reply #6 on: August 06, 2013, 08:49:04 pm »
Where did you get the front posts from ?

They look HP alike  :-+

Just noticed http://www.rapidonline.com/  their product numbers 17-3270 and 17-3271. Looks very similar to the HP part.
 

Offline george graves

  • Super Contributor
  • ***
  • Posts: 1257
  • Country: us
Re: HP 6632A fan replacement and front panel posts
« Reply #7 on: June 23, 2014, 05:27:40 am »
Interesting temp controlled fan.  But isn't that fan blowing air *into* the heat sink, and getting it's air from outside (more of less)???

Looks like the fan's sensor in built into it, so how does it know when it needs to ramp up?



Offline AlfBaz

  • Super Contributor
  • ***
  • Posts: 2187
  • Country: au
Re: HP 6632A fan replacement and front panel posts
« Reply #8 on: June 23, 2014, 09:18:56 am »
Looks like the fan's sensor in built into it, so how does it know when it needs to ramp up?
Shame the one photo I was interested in is over-exposed. that being said isn't the yellow wire possibly the temperature sensor?
 

Offline george graves

  • Super Contributor
  • ***
  • Posts: 1257
  • Country: us
Re: HP 6632A fan replacement and front panel posts
« Reply #9 on: June 23, 2014, 09:39:18 am »
I think the yellow wire is for PC type motherboard RMP detection.

Offline Andy Watson

  • Super Contributor
  • ***
  • Posts: 2142
Re: HP 6632A fan replacement and front panel posts
« Reply #10 on: June 23, 2014, 09:46:13 am »
But isn't that fan blowing air *into* the heat sink, and getting it's air from outside (more of less)???
Looks like the fan's sensor in built into it, so how does it know when it needs to ramp up?
Yes, the fan does blow into the heatsink. I don't know how the OP has wired his new fan, but manual has this to say about the fan control.
Quote
The fan driver control circuit provides the DC voltage to operate the cooling fan. The Fan_Prog signal from the secondary interface circuit varies this voltage according to the ambient and heatsink temperature as well as the output voltage and current of the supply."



 

Offline mzzj

  • Super Contributor
  • ***
  • Posts: 1299
  • Country: fi
Re: HP 6632A fan replacement and front panel posts
« Reply #11 on: June 23, 2014, 10:29:42 am »


Quiet now! Even when drawing full power the fan is barely audible.  My lab bench is in a walkout basement utility room where the ambient temp is usually in the mid 60s F - so I doubt this fan will ever need to crank up to full speed.

Just to be sure I would measure the heat sink temperature after 30 mins or so full load(max current to short-circuit).
6632A/B has rather special output stage resulting in massive idle losses and even worse full-load losses. 

 

Online nctnico

  • Super Contributor
  • ***
  • Posts: 28488
  • Country: nl
    • NCT Developments
Re: HP 6632A fan replacement and front panel posts
« Reply #12 on: June 23, 2014, 11:29:20 am »
I agree. Mounting a fan which doesn't provide the designed airflow is asking for trouble. OTOH HP power supplies usually have temperature protection which kicks in soon enough.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline macboy

  • Super Contributor
  • ***
  • Posts: 2315
  • Country: ca
Re: HP 6632A fan replacement and front panel posts
« Reply #13 on: June 23, 2014, 12:34:08 pm »
A temperature controlled fan is only effective when it is subject to the hot air that it is meant to exhaust. In your case, the fan is operating as an intake fan for the heatsink (it pushes air into the heatsink). It should be pulling hot air out, not pushing cold air in. Otherwise, it is operating based on the ambient (cold side) air temperature, not the hot side temperature.
 

Offline mtdocTopic starter

  • Super Contributor
  • ***
  • Posts: 3575
  • Country: us
Re: HP 6632A fan replacement and front panel posts
« Reply #14 on: June 23, 2014, 12:59:33 pm »
We'll, I'm in Montana right now and about 1000 mi from my lab so I won't be able to check until next week, but I sure thought I had mounted it to produce air flow in the same direction as the original. It sure doesn't look that way in the pics, does it!

I may have reversed it after I took that pic. I honestly don't remember - it was quite a while ago.  :-//

The yellow wire has nothing to do with the temp control. IIRC, the fan has a thermistor mounted near it's center on the intake side. Since you can't see it in the pic it makes me think the fan might actually be pulling air out of the heat sink as pictured despite the orientation of the blades.

I can say that it's worked fine since the install including when used as an electronic load. But as I said earlier the ambient temp in my lab is usually on the cool side so maybe I've been lucky.

I'll investigate more next week.
« Last Edit: June 23, 2014, 01:02:18 pm by mtdoc »
 

Offline macboy

  • Super Contributor
  • ***
  • Posts: 2315
  • Country: ca
Re: HP 6632A fan replacement and front panel posts
« Reply #15 on: June 23, 2014, 01:10:28 pm »
We'll, I'm in Montana right now and about 1000 mi from my lab so I won't be able to check until next week, but I sure thought I had mounted it to produce air flow in the same direction as the original. It sure doesn't look that way in the pics, does it!
...
It looks like you mounted it the same way as the original, blowing air into the heatsink (and out the back of the unit I assume). That is the way the original fan was designed to work, but it wasn't a temperature controlled one. My point was that you can't really use the temperature controlled fan in this application, because the fan is on the cold side, not the hot side. If you could pull the thermistor out, and extend it to the hot side with a pair of wires, then it might work well.
 

Offline mtdocTopic starter

  • Super Contributor
  • ***
  • Posts: 3575
  • Country: us
Re: HP 6632A fan replacement and front panel posts
« Reply #16 on: June 23, 2014, 01:23:06 pm »
It looks like you mounted it the same way as the original, blowing air into the heatsink (and out the back of the unit I assume). That is the way the original fan was designed to work, but it wasn't a temperature controlled one. My point was that you can't really use the temperature controlled fan in this application, because the fan is on the cold side, not the hot side. If you could pull the thermistor out, and extend it to the hot side with a pair of wires, then it might work well.

That may be. As I think about it more I do recall pondering that issue a year ago when I did this. I do remember testing the temp response of the fan with a hot air gun.

I can say that the fan speed does vary depending on the load and the unit has been working flawlessly.

Lying in a tent, typing this on my phone whose battery is about to die...
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf