Netonix Forums

I have this project that requires a DC fiber switch, but I'm am questioning my choice in enclosure. Is this aluminum box big enough to dissipate the heat? It will only be powering 1 Powerbeam and the SFP module. There is a possibility that I might add another radio in the future, but for now that's it. Also it will be fed by 48vdc, if that makes a difference.

I don't know but I would put in a couple vents, at least 1 high and 1 low:
https://www.google.com/webhp?sourceid=c ... +box+vents

Also make sure you paint white

Could put 2 of these top of door face and 2 bottom door face?
http://www.alliedelec.com/bud-industrie ... DQodeLUPYA

hmmm...not bad, I think I will do that. Thanks

1: for best heat/power efficiency, feed with 24v; just the nature of our DC-DC converter. 48v isn't significantly worse, but 24 is optimum.

2: the way you're mounting, the fan isn't going to be doing much. Active airflow may not be strictly necessary, but if you can find a way to get that fan pointed at more open air, do so.

3: only way to know would be testing. Switch is load tested (with a much higher load than you're implementing) for some time at 90C ambient (I believe, dave, chime in if i'm wrong); Knock it together, power it up, and stick it outside for a couple sunny days.. maybe snmp alert on temps over 90 and again over 95, but almost everything on that board is rated to 100C, and what isn't, doesn't produce much heat. Either way, let us know how it goes.

My experience suggests seeking another option. Optics can run 20-25C hotter than the host board and tend to get shaky above 65C. So if the enclosure hits 40C and the switch is at 50C, you have a problem. Find a Finsar SPF that will meet your needs and ensure your supplier sends you Finsar. They typically run +4C. If you get past 70C on the switch I'd expect issues with errors. For a single PowerBeam I'd use the following and rate it to 70C, Take the PC board out of it's plastic shell and affix heatsink fins to the SFP cage. Mount assembly to box with standoffs -

https://routerboard.com/RBGPOE-CON-HP

https://routerboard.com/RB260GSP

https://www.arrow.com/en/products/ftlf1318p3btl/finisar

If you need to vent the box, use -

http://tyconsystems.com/documentation/S ... 0Sheet.pdf

I would not take the switchboard out of the chassis.

1 it is not plastic it is metal.
2 our chassis has a fan and airflow is important.
3 we have tested the switch to operate fine in up to 55C environment under full load and the test oven is small with no air flow just HEAT.

Now he does have a point that whatever SFP module you use it could have a thermal problem but once again we are blowing air around with the fan so that helps a lot. I do not think our unit would have any more of an issue with SFP optics than say the UBNT Edgepoint, in fact ours would probably do better as we do have a fan and there is airflow over the SFP module even if it is in a small box.

I do think venting the box is a must since it is this small and my suggestion and the ones above are all good options for box vents.