PC inside the Control box...GOOD or BAD idea?

[rotorzoomer]

I am at the Mechmate control box planning stages and wanted other fellow MM builders thoughts on whether it's a good idea to mount a stripped down PC inside the control box like others have done?

The idea seems good on the surface, but am i setting myself up for trouble and issues i don't know about yet while trying to pursue a consolidated electronics box?

[sailfl]

Mark,

I think it is a bad idea though there have been some people that have done it and are not having any problems.

There is enough heat in the controller box with out adding the heat from a computer plus computers don't like heat.

As far as I am concerned, the bigger the controller box the easier it is to work on and less heat.

One guys opinion.

[MetalHead]

I also think that by keeping it seperate the PC will be easier to service. If you custom build the case to hold the MoBo then you will be restricted to that foot print if the MoBo fails.

But you can do it. This is after all that kind of place :D .... and we loooove pictures of the process.

[riesvantwisk]

I can second Nils his opinion,
I had a old laptop in my control-box that did go into thermal shutdown 3 times. The old laptop had one ventilator not working, on my desk installing EMC not a problem but in my control box not so much. I did add a extra ventilator on my laptop and a ventilator to remove heat from the control-box through a air filter.

The advantage of having it in the control-box is less cables and less boxes to buy. I didn't had issues with noise or erratic behavior of the machine, and I don't have any screened cables.

Ries

[rotorzoomer]

After reading countless posts, it was very easy to get lured into some brilliant designs such as the ones below.

[melissa]

Blimey, those are some huge PC's (nevermind the power supply!).

IMHO a mini-ITX motherboard is a better option -- I bought mine from http://www.logicsupply.com/

From my build thread: Quanmax KEMX-2130 mini-ITX motherboard. Pentium 4, 1.6 GHz with 2GB of memory. This will be located in the control box. The ATX power supply is about the same size as the ATX connector.

http://www.mechmate.com/forums/attachment.php?attachmentid=8745&d=1267664854

Michel

[rotorzoomer]

michelg....That's exactly the type of PC i was thinking about using, the so called Small Form Factor PC with smaller motherboard and power supply with all other connectors stripped out. It still packs a punch, it runs a Pentium IV 2.8Ghz Hyper Threaded with 1gb RAM and 40gb SATA drive.

The heat is non negotiable still, i run a few of these in the office and they do get warm even in this size.

[swatkins]

I have been using Shuttle computer cases for a long time now.. They all have a heat pipe system that mounts to the CPU and has a remote radiator... This method is used because the small form factor case is very tightly packed and there is no room for a large CPU heat sink and fan, as is normally used...

On the Shuttle they mount a fan on the radiator but I have seen designs for heat pipes that are passive.. Here is a site (http://www.silentpcreview.com/article114-page2.html) that has a DIY heat pipe that could be easily made to fit our control boxes and would move most of the extra heat to the outside of the case...

[KenC]

I toyed with integrating the PC into the control panel & after a torturous experience, I eventually gave the PC its own chassis. As I feel my panel is over crowded for trouble shooting & future maintenance work. Also the only cable affected is the parallel port cable. Also I don't see the advantage in compact footprint.

There is nothing wrong with integrating the PC into the control panel as long as you know what you are doing.

If you choose the integrate path, do get a chassis that is big. As big as you think it is insane.

The greatest different with integrated PC is aesthetic &
"because you can" or "because you want to" ;)

[J.R. Hatcher]

I was the first to incorporate the computer inside the control box, that was over 2 years ago. I have never had any problems associated with this setup. I have included a few links to some pictures.

http://www.mechmate.com/forums/showthread.php?p=9871&postcount=264

http://www.mechmate.com/forums/showthread.php?p=9931&postcount=272

My next control box will have a shelf mounted to the door and the computer will just sit on the shelf.

[DMS]

Sorry Guys,
I could not resist.
Here is my link http://www.mechmate.com/forums/showthread.php?t=556
have no issues regarding heat or noise, more than 1.5 yrs passed. Hours of daily work.
The temperature in Rajasthan now a days is around 45 C, causing no harm to electronics. (No AC installed :) )

[rotorzoomer]

Going crazy trying to distinguish between positive / negative air pressure and as Gerald suggested along with other forum members POSITIVE pressure is the way to go?

In which direction does the air flow in this picture?



http://www.mechmate.com/forums/attachment.php?attachmentid=7758&d=1260994737

[jhiggins7]

Okay, I'll give it a try...

The direction of air flow depends on whether the fan on the right side of the box is "exhausting" air or "in-taking" air. If it is exhausting air, the air flows in through the filters and out through the fan. This creates a "negative" air pressure inside the box.

If it is in-taking air, air flows into the fan and out through the filters. This creates a "positive" air pressure inside the box. However, in this case the filters would not protect the inside of the box.

[rotorzoomer]

I think Gerald made mention in a post that a filter also goes on the fan side and where those paper filters go is the exhaust which may technically mean nothing goes their except a hole / vent.

[Gerald D]

In the direction of the airflow you need:

Filter -----> Fan ------> Box -------> Exhaust, for good positive pressure of clean air.


(In the picture you have either:
Filter -> Box -> Fan -> Exhaust (negative pressure, dust enters around door and fittings), or
Fan -> box -> exhaust -> filter (positve pressure, but dirty air going inside)

[rotorzoomer]

So essentially positive pressure means spending all your time and money on the fan / filtration system combination blowing air inwards so by the time the air enters the control box it's filtered then escapes via a hole in the opposite direction.

Does the exhaust need any filtration or is it just a normal vent hole?

[Gerald D]

The exaust is just a hole, but not too big. It must cause a bit of resistance to the fan's pressure so that a bit of "positive pressure" builds up inside the box. If the exhaust is too small, too little air will move through the box to have a cooling effect. If the exhaust is too big, dust can enter the door seals, or even the exhaust. Generally, the exhaust is a hole at the bottom of the box, or a hole covered by downward facing louvres.

The interesting exercise is to cover the exhaust completely with paper and masking tape. If the system in the box does not get hot, then you can remove the fan and filter and close all the holes. ;)

[liaoh75]

Sorry guys, but I must have missed the "positive pressure" lecture. Can someone direct me to the thread this was discussed? My system is working just fine. I have two fans. One for intake and one for exhaust. Everythings been working just fine for quite some time. I have a filter on the intake side but nothing on the exhaust side. I've got a lot of airflow and the PC stays cool. I watched it like a hawk for several weeks last summer when the shop temperature peaked.

[Gerald D]

David, if you disconnect your exhaust side fan, then you will have a genuine "positive pressure"......but, why scratch where it doesn't itch? :)

[makindue]

I am at the Mechmate control box planning stages and wanted other fellow MM builders thoughts on whether it's a good idea to mount a stripped down PC inside the control box like others have done?

The idea seems good on the surface, but am i setting myself up for trouble and issues i don't know about yet while trying to pursue a consolidated electronics box?

I've done a mount a stripped down PC inside the control box. For me it is a good idea. :cool: