UcD400 Q & A

[Bruno Putzeys]

I would hesitate to count on the heat getting to the side walls all the way from the back panel. Simple thermal calculation may illustrate this. Assume a heat source is placed in the middle of a 360mm x 70mm x 2mm plate, and actual heat sinking takes place on the end. This is equivalent to a 180mm x 70mm x 4mm plate with source on one end and sink on the other.
Thermal conductivity of aluminium is around 200W/mK.
200(W/mK)*0.07(m)*0.004(m)/0.18(m)=0.31W/K or 3.2K/W.
At idle, 5 UcD400's dissipate around 30W. Although the situation is a bit better for the modules placed more to the sides, you will recognise this is becoming a problem.

In short, try to find a way of mounting the modules on the side walls. That one side wall will sport 2 modules and the other 3 is an aesthetic issue you'll have to live with.

[UrSv]

Not a big problem. Just buy one more module and there's three on each side. One can always use another channel...

[FransDHT]

Bruno,

Thanks.

But is it possible to put them above each other on the sidewalls, Will there be enough airflow for them being close together? Should I put them with the PCB toward each other, away from each other, or the PCB's facing the same way?

This should for example look like this

Frans

[FransDHT]

And to the sidewall with two modules like this.

Frans

[chrisb03]

Originally posted by FransDHT
And to the sidewall with two modules like this.

Frans

FransDHT, I think your pushing your luck in thinking you will get it all the gear into that enclosure. Either get a bigger one or two separate enclosures. You will find you may have to add something additional in the future and you wont have the room. I wouldn't put the modules one on top of the other as the bottom one may radiate extra heat to the top one.

[matjans]

and effective aircooling i think is needed for the output coil, which you are effectively taking out of a fresh-air-loop ...

[FransDHT]

chrisb03 and matjans,

I know, I know, but the problem is that I like this enclosure. I don't want it higher (and there is no need for that). I would like it deeper, but I don't know where to get it.

I have seen enclosures at Conrad adn Monacor, but they are not aluminium (and have no cooling sides) and I read somewhere that that is needed.

This is maybe a way to keep the air flowing? Four to one side, one at the other:


Frans

[Jan-Peter]

Small suggestion;
Place all modules vertical instead of horizontal. The minimum height what you need is 76mm. Put the UcD400 in such a way that the coil is on top, because the coil is having the highest temperature.

Regards,

Jan-Peter

[Bruno Putzeys]

Actually this last arrangement (diagonally) isn't that bad. Make sure you have ventilation holes in the bottom and the cover of the case, otherwise you still won't have any air flow.
Most of the heat comes off the T block, so these two measures should keep the modules happy.

[Bruno Putzeys]

Originally posted by Jan-Peter
The minimum height what you need is 76mm.

Yeah, I figured so too, but then I remembered his box is only 70mm