Waterproof box for J1SYS P12S board and 2 power supplies

logandc99 said:
plasmadrive said:
You guys do know that those supplies are not meant to be mounted in that tight of an enclosure, right? I suppose if you only play flashy blinky you should be ok since the duty cycle is pretty short, but man It sure seems weird watching everyone post about something that is so not right... LOL :p
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It's always great to get constructive criticism ..... although sometimes it can be tricky spotting the constructive part.
For those of us "playing flashy blinky" and making such "weird" and "so not right posts" about the enclosure setups, it would be great to get a pic of one of your enclosures with power supplies and ventilation so we can see how it should be done. It's would also be great to get an idea of what the temp should be kept below within the enclosures to make sure the power supplies don't get damaged. The air temp tops out at about 18 degrees Celsius when the lights go on here around 9pm. As stated in an earlier post in this thread ( a reply to a constructive query), I have ventilation at the base of the enclosures ( see pic below) but I am assuming from your comment that this is clearly not enough.
Look forward to seeing pics of your setup and getting some details about where I am going so wrong.
Any other helpful feedback from others on this matter is also greatly appreciated.

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I just figured out how to find posts that I replied to.. Sorry for the delay.
The reason it is weird for me is that I have a UL 508A industrial panel shop. We have to build everything to worst case. I am just not used to seeing power supplies crammed in such small boxes.
As an engineer I know these setups are far outside the normal conditions that these supplies are made to handle, but I also understand that due to the nature of what we do in this hobby we don't stress the components even close to their max (for the most part). that is why my qualifier about "playing flashy blinky"

You wanted to know what I do for my supplies, OK.. I cheat, I use real wet location rated power supplies and let them be outside in the weather. I also use weather proof DC-DC converters for lower voltages. I know everyone can't do that, but this is what I do.

And BTW, I got about 100 of those supplies thinking I would help the hobby guys with low cost supplies.. I have been selling them to many for very cheap... so I am trying not to just sit on the side lines and watch. :eek:
 

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A couple of other notes about my comments and the supply scheme used by many.

The supplies you are using should come with over temp shut down built in. (instructions should clarify). So if they get too hot, they "should" shut themselves down. If you are not having that issue, you are most likely OK, or the shut down is not working right.

I also bet they are not rated above pollution degree 2 which means that if you are in a wet environment, perhaps you might expect some issues over the long term which could cause failure. The month of so they are outside in those boxes might render that a non issue for this application... but the fact remains this is something to at least think about and/or be aware of. http://www.ni.com/white-paper/2871/en/

If you want to get the best airflow, you should have specific intakes and outlets. The air from the outlet should not recycle to the inlet. Those supplies have fans so they will pull air thru them. Kevin at Creative came up with a pretty simple idea that looks pretty clean. http://www.store.creativelightingdisplays.com/CMB24D-RGB-DC-Controller-ReadyToGO-No-Assembly-CMB24D-RGB-RTG.htm
This would allow air to flow thru from bottom intake to the front face outside. Of course that means pulling in any ambient moisture with the air. May or may not be an issue for some.

"Generally" supplies like that state that they require a specific amount of space in between when mounting multiples in the same enclosure. That would be in their "conditions of acceptability" or instruction manuals assuming they have one.

OK.. those are some of the things that I have to watch for when building control panels for others.. But.. as hobby guys and gals, we tend to be able to get away with far less generic solutions and more "customization" since we are not selling to the world at large. Again, my qualifier of "playing flashy blinky"... but I still cringe because I have seen the failure that can happen with those supplies. Not saying they will happen to you but now you have my reasons...

You asked for constructive.. here you go. Information you can use if you choose. Hope it helps in some way.
 
Thanks plasmadrive. Definitely some good constructive info there and the kind of stuff I think we all want to hear when someone expresses concern about different setups. The link to Kevin's website was interesting to see with the air out vent on the front panel. Just wasn't sure where the air intake was on the enclosure setup as I noticed that he still had the holes at the base of the enclosure blocked off with the sponge rubber. ( unless the sponge rubber lets in more air than I think but it seemed quite dense in the boxes I got from him some time ago).
 
Kevin removes the bottom sponge I think.. That is what we talked about in a thread on the LOR forum. That is about the only way to get enough air flow. I know he also relies on some of the air coming in around the door since there is no seal.

His vent has louvers and a bug screen. The louvers for the rain. I recommended he put a sticker on his supplies stating the mounting orientation of the box since being laid on their back would make the louvers about useless.
 
First of my many boxes being modified for increased airflow.


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Yes the enclosures are either in places not exposed to the elements or if outside are placed under much bigger storage boxes that are just turned upside down to sit over the enclosures.
 
logandc99 said:
First of my many boxes being modified for increased airflow.
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That is a start, however, if that fan blow into the back of the vent, you will most likely get a pretty high degree of hot air just running around inside the enclosure. Much of that air will hit the back of the filter and just bounce back inside and be recirculated thru the supply. A better solution would be to use something like what Kevin did where he created some what of a vent path to the outside. Forcing the air out of the enclosure with no possible way back in would be far better. That would force fresh air from the outside into the enclosure from the intake, wherever that happens to be.

Just my $.02 worth.
 
I have replaced the foam that came with the filter with the same mesh material that I have used for the lower vents, and in testing, airflow out of the vent feels very good.
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logandc99 said:
I have replaced the foam that came with the filter with the same mesh material that I have used for the lower vents, and in testing, airflow out of the vent feels very good.
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That certainly helped for sure, but I would venture you are not getting as efficient of a transfer as you might like. But it since the type of load we use is pretty intermittent, I am guessing you might be fun as long as the ambient heat doesn't get to hot. I any case, baring it's failure, the over temp cut off in the supply would most likely shut it down if it got too hot anyway..
 
The enclosures with one power supply in them have their power supplied inbuilt fans directly beneath the vent and air seems to flow quite strongly out through that vent. The enclosures with the two power supplies currently have only one central vent in the front of the enclosure but my plan is to attach a 12v fan to that central vent to force air out if the enclosure ( that is, as soon as I get back to Jaycar to swap the fan I bought yesterday which is too small)
 
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