Fan in an electrical cabinet

[craigsimon]

Thermoelectric solid state coolers

I think GSI1 was getting at is the Thermoelectric solid state air conditioners. My company is just now getting into producing these, so wait about six monthes before you use any. I am new to them but what they are in a nut shell is thermocouple working backwards. You supply DC power to them and they will heat on one side and cool the other. No moving parts other then the fans for the air flow. Here is a web site that contains info.
http://www.eicsolutionsinc.com/800.htm
The pricing is not much, if any, different then a "normal" air conditioner. The advantage is the noise level and no mechanics.

 

[Tom Jenkins]

Any AC is going to have fans and filters of some kind. We've used Melcor A/C unit www.melcor.com. Another neat rig I just ran across is a air to air heat exchanger using heat pipes from Noren www.norenprodcts.com. I haven't used them yet, but they look pretty neat.

 

[Steve Etter]

Well I just got off of the phone with EIC Solutions who (like craigsimon's company) sell a line of thermoelectric solid state air conditioning units.

I specifically asked and the salesman told me that the unit he quoted me (AAC-140B-4XT-HC) requires no type of filtration or cleaning in most environments (they do have fans but no air is exchanged between the cabinet and ambient environment). He described what he called his "worst" environments (lots of particles and oil/moisture in the air) and indicated that the cleaning practice for these units is to wash them down with high pressure water.

I think the price he gave me is a little high ($1000+), but for my current project I think I will buy one anyway.

Steve

 

[Tom Jenkins]

Let's try this again: www.norenproducts.com

 

[David_Emmerich]

I would have to second the idea that fans/filters don't work as planned...the filters can leak, etc. If you have the lurury of being able to not croud the panel, and your heat load is not to high, 'enhanced' natural cooling is most often the best way to do it.if you have big heat sinks inside your panel, try to cut and mount them so that the fins are outside the box, with a good gasketed seal . Put the transformers up high, the i/o field wiring up high(makes it easier to termanate, too) and the PLC's lower in the box, with a small fan under it . Unless you are next to an oven or a steel strip line, if the room is cool enough to work in, the box SHOULD be ok.... Just my thoughts though.
David
beerchug

 

[jdbrandt]

peltier coolers

Teco is the name of the company, I think, that makes the
solid state air conditioners.

They do work, but, they are expensive, initally.

 

[Shaun]

Hi Rick,

I would use Jesper's idea or not cooling at all.
If your spacing is good between your PLC and other devices, this is the main control. You have a power supply and I am assuming a small coil on your starter that generate heat. If you can move the power supply away from the cpu that would help too. Using solid state a/c requires power and probably dc power, so now you have to add a power supply another item that can fail, generates its own heat, and also you may need a separate 120VAC source for this.

Having the plc power supply will actually help your panel. Keeping your panel just warmer then the outside of your panel will keep it nice and dry (no condensation). Check you temperature ratings outside the panel, if they are not too extravegent you will be find it ok, also check the plc temp ratings.

About the spec, unfortunately a lot of spec writers choose to cookie cutter other specs or pieces of specs without actually spending the proper time for a real good practical spec. Contact the spec writers and explain the situation, explaining that it may introduce problems having the filters and explaining a really good solution with actual facts will help you be able to 'take exception to that part of the spec'.

hope this helps

I design plc panels by the way.

cheers

shaun

 

[Rick Densing]

I wasn't planning on putting the fan in, and now the customer agrees for this application.

I was just soliciting opinions on fans in general.

Thanks anyway.

 

[shooter]

Keep all connections on bottom side close the cabinets firmly
if too hot inside use some small fans to circulate it inside, if still too hot use closed cooler in door or side.
do not put compressed air inside, as it will be dirty.
a little dirt is no problem as the contacts do need some grease.