Following is a recent e-mail transcript between myself and a potential client and his concerns about using a Cabinet Cooler System.
I have gone through your web. We need a Cabinet Cooler System for our CNC panel. I have lots of question in my mind regarding cabinet cooler.
1) What is force of air inside the cabinet?
Depending on how tight the cabinet is, pressure can build up to about 2 PSIG maximum.
2) How can we control condensation?
The source of condensation would be from the air outside the cabinet, not from the Cabinet Cooler System itself as is often mistaken. As long as you have the cabinet cooler installed properly and have closed off all vents / fans from pulling outside air into the panel, you will have no difficulty with condensation.
It is also worth mentioning that we are not trying to create a refrigerator-like atmosphere inside customers’ electrical panels. Generally, we maintain a target temperature of 95°F (35°C) inside the enclosure, so there is not any real opportunity for condensation to form as a result. In fact, the original volume of air within the enclosure is purged out of the box about 3 times or more during the first few minutes of operation.
3) Humidity affects the electronic circuits – How do we prevent it?
As mentioned in #2 above, when you install the Cabinet Cooler System properly and close off all vents, the enclosure is then purged with clean, dry air. Humidity level within the cabinet will drop to a range of about 45% which is considered dry enough for cabinet cooling purposes. And so, the conditions within the cabinet are such that no condensation would ever have chance to form inside the enclosure.
4) Where does the exhaust air go?
Exhaust air flows out of the cabinet through the Cabinet Cooler. It has its own vent incorporated into the mounting base. Cold air is delivered through center opening, cabinet air exhaust vents out through a perimeter vent on the base of the cabinet cooler.
5) What is the air consumption?
The air consumption will depend on how much heat load you have in the application but the general range is anywhere from 8 to 80 SCFM @ 100 PSIG to produce cooling powers from 550 Btu/hr up to 5600 Btu/hr. And note, this is only when the thermostat calls for cooling due to the heat load within. So, the Cabinet Cooler System will only use the energy necessary to keep the enclosure at desired set point and no more.
6) Air solution is 3 times more expensive than electricity. How we can save energy?
Utilizing thermostat control is the best way to limit energy use to that only required to maintain desired set point inside the cabinet. We normally work to a 95°F (35°C) set point. This might seem a bit high to the novice user but electronics can live comfortably at this temperature. Remember, we are cooling electronics and not human beings.
When a customer is looking at an EXAIR Cabinet Cooler System, they are taking into account a lot more than just the cost of energy in their purchase. It is no secret that Freon based air conditioning units are fairly efficient at cooling. The problem with them is that they are a huge maintenance issue for those companies who have them. With the factory environment being much dirtier and hotter than a typical laboratory or office, Freon coolers do not stand up to the excessive heat, dirt, moisture, and other contaminations that reduce their efficiency and reduce their effectiveness to a critical point where they fail. (A point that no Freon air conditioner cooler manufacturer is going to admit to).
So, I ask you, what happens when you experience a component failure in a cabinet with a Freon based air conditioner that has failed and you don’t know about it until it is too late? Not only are you out the cost of the repair for both the air conditioner and the failed component(s) inside the cabinet, but also the lost production. So, you are paying more money for repairs, lost production, saving face with your client due to lost production, etc. etc.
What we are selling with our Cabinet Cooler is hassle-free, and virtually maintenance-free operation. When fed with clean, dry, oil-free air, EXAIR Cabinet Coolers operate indefinitely with little input from your maintenance crew. Another benefit of the vortex cooler operation is that the panel is pressurized a bit so as to keep out any dirt, dust or other harmful debris from getting into the cabinet. Many customers involved with materials in their production that tend to be powdery in nature find this feature quite useful. Freon air conditioners placed in the same scenario simply end up with clogged filters and burn up due to low airflow. Click here to check out a quick comparison.
7) Air creates the noise. Will your coolers increase the noise pollution?
Compressed air does create noise when used. This is a fact of life. EXAIR does take every step possible to keep the sound level of our Cabinet Cooler Systems at a reasonably low level. We market the use of our Cabinet Cooler Systems for industrial or factory type applications. Use in a lab or in an office setting is possible, but is not the normal use. When placed on the shop floor or near a large oven, boiler, stamping machine, or mill you would not even know when the unit was operating and not. If you want to know the actual dB rating for each Cabinet Cooler System, you can follow this link.
8) My air compressor has 650 CFM capacity. Your product will consume air from a main air line. Continuous air leakage can’t build the pressure in the reservoir and it’s a costly solution for us.
You write as if you expect our Cabinet Cooler System to take the full capacity of your compressor. Nothing could be further from the truth. Our Cabinet Cooler Systems are designed to turn on and off as needed to accommodate the heat generated within the application. In other words, it is not a constant leak as you have described. And to describe the flow through our Cabinet Cooler System as a leak really gives false indication that it isn’t doing anything. The Cabinet Cooler System IS doing something. It cools the electronics in your cabinet to keep the cabinet up and running so your process does not break down. If you want a high degree of reliability in this sense, great! Consider using a Cabinet Cooler System. Do away with the constant headaches of dealing with repairs to Freon coolers and the electronics inside the boxes they are supposed to be cooling. If you are hyper concerned about only energy use to the neglect of the other costs associated with running Freon based coolers, this is a common mind-set that we encounter in our discussions with customers. You are going to spend money to run production. It is your choice how much of that goes into energy use and how much is dedicated to fixing things that break down. Which would you rather do?
It is my job to point out to you that energy use is NOT the only cost that goes into the decision of what to buy when it comes to cooling equipment for this purpose. I hope I have pointed out a few reasonable issues for you to consider.
9) Main compressor is running continuously to generate the adequate air pressure.
If your compressors are “at capacity”, you should consider a program to have a more efficient operating system. Up to 30% of the average compressor’s capacity is lost through leaks in the piping system alone (in your system that would be up to 195 SCFM!). If you could save almost 1/3 of your compressed air by simply fixing leaks, would you do it? We have products that can help you get a handle on locating and fixing your leaks and also to monitor your air use for any given pipe line in your facility from ½ inch up to 6 inch pipe. Take a look at our Optimization Products
If you have applications where air is being used for things like blowing and cooling, chances are, we have other products that can help you to reduce that air usage too (Air Knives, Air Nozzles, Air Amplifiers). If you have things like open copper tubes, steel pipes and pipes with drilled holes performing blowing within your applications, we have products that can cut down on air use, lower sound levels, and bring you into compliance with OSHA dead end pressure requirements. It’s a matter of management taking the time to implement an air savings program to endeavor to save air (energy) use. There are other things that can be done on the compressed air production side of things in your plant as well to increase efficiency. Following is a link to an on-line magazine that perhaps you should review to get better ideas of what I’m talking about. http://www.airbestpractices.com/