EXAIR Gen4 Power Supplies

Static Elimination is a big call for us. We have many amazing products that will eliminate your surface static with ease. Static can cause so many issues, we could (and have) write several blogs on this alone. EXAIR’s Gen 4 static eliminators (also called ionizers) can eliminate static charges. These shockless ionizers are electrically powered and produce a plethora of positive and negative ions. The charged surface then attracts the appropriate number of positive and negative ions from the ionizer to become neutral, or discharged.

The key behind this is the high voltage power supplied to the Ion Points. The power supplies that we offer, are the only power supplies that are compatible with our ionizing products. Each outlet supplies 5kV. This high voltage powers the Ion Points in the products to create the Ions mentioned earlier.

The power supply is sold with either 2 or 4 ports to power that many Gen 4 Products. Each one has a selectable input voltage of 115VAC or 230 VAC, an input current of .2/.1 A max, and a frequency of 50/60Hz. They also have a lighted power switch for easy visualization of power. This light is on a rocker switch, and this can be replaced – here is a blog to do this: How to replace the rocker switch on the Gen 4 Power supply.

Each power supply also has an integral fuse to protect against power spikes, and these can be replaced if necessary. Here is a blog link on how to do this: Video blog to change fuse on Gen 4 Power Supply.

The power supplies each come with a 6′ electromagnetically shielded power cord to plug in the wall, or to hardwire into your machine. The power supply cases are shielded as well.

All of our Gen 4 Power Supplies are UL component recognized to US and Canada safety standards, and are CE and RoHS compliant.

Please feel free to reach out if you have any other questions about our Gen 4 Power Supplies, any of our Static elimination products, or any of EXAIR’s intelligent compressed air products.

Thank you for stopping by,

Brian Wages

Application Engineer

EXAIR Corporation
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What You Can Do With A Vortex Tube…And What You Can’t

Vortex Tubes are near the top of the list of the most interesting uses of compressed air: Cold (and hot) air, generated instantly, from a device with no moving parts. Why don’t we use them for EVERYTHING? It’s not that it CAN’T be done, but it can be impractical to do so. Consider:

While researching our Cabinet Cooler Systems, some callers will ask about using this technology to cool a space larger than an electrical panel, like a server room. I spoke with just such a caller once, who had 7.5kW worth of heat estimated in a server room that was under construction, and had been asked to research cooling solutions…so we did:

  • Since 1 watt equals 3.41 Btu/hr, 7.5 kilowatts equals 25,575 Btu/hr worth of cooling required.
  • Our highest capacity single Cabinet Cooler generates a cooling capacity of 2,800 Btu/hr, so we talked about ten of them, for ~10% safety factor, which was reasonable for the purposes of our discussion.
  • Each 2,800 Btu/hr Cabinet Cooler uses 40 SCFM @100psig, for a total of 28,000 SCFM. Using a common thumbrule that says a typical industrial air compressor generates 4 SCFM per horsepower, that means they’d need a 100HP compressor (or that much capacity from their whole system) just to run these Cabinet Coolers. Adding that cooling capacity to their HVAC requirements made more sense.

Of course, with every rule, there’s an exception: an independent crane operator carries a Model 3250 Large Vortex Tube with him for cab cooling in the tower cranes he’s contracted to operate. While the US Department of Energy considers “personnel cooling” to be an inappropriate use of compressed air, the small fans typically found in these cranes’ cabs offer little comfort to an operator spending all day, 50 feet off the ground, in the summer heat of the Deep South!

EXAIR offers 24 distinct Vortex Tube models with cooling capacities from 135 Btu/hr to 10,200 Btu/hr.

Another common question regards the use of a Vortex Tube with another EXAIR product…the most common being an Air Knife. These callers want to blow cold air onto something, but instead of the conical and relatively small flow pattern the Vortex Tube discharges, they want to blow a curtain of cold air. The design & function of both the Vortex Tube, and the Air Knife, work against this idea:

  • The cold air has to exit the Vortex Tube at, or very near, atmospheric pressure. If it encounters much back pressure at all, performance (as measured by the temperature and flow rate of the cold air) will deteriorate.
  • An Air Knife, by design, is pressurized all the way to the point where the compressed air flow exits the 0.002″ thick gap. That’s far too much back pressure for a Vortex Tube to operate under.
  • Even if the Vortex Tube DID supply cold air, under pressure, to the Air Knife, the tremendous amount of environmental air entrained by the Air Knife would still result in a total developed flow temperature that was much closer to ambient temperature for the area.
Since the Super Air Knife entrains air from the surrounding environment at a rate of 40:1, the resultant air temperature, regardless of the temperature of the air supply, is always going to be pretty close to ambient.

One “workaround” for this is what we informally call a “cold air knife” – that’s when you plumb the cold air from a Vortex Tube into a length of pipe with a series of holes drilled along its length. Let’s say a building products manufacturer wanted to blow cold air across a 10ft wide continuous sheet of roofing material…because they did:

  • I recommended that they take a PVC (because it’s non-conductive and wouldn’t transfer heat from ambient as fast) pipe a little longer than 10ft, cap the ends, drill 1/8″ holes every inch (total of 120 holes).
  • From the table below, we see that a 1/8″ diameter hole can flow as much as 1.1 cubic feet per minute @1psig*, so 120 of those holes will pass ~132 cubic feet per minute worth of air flow.
  • Four Model 3240 Vortex Tubes were specified: when set to an 80% Cold Fraction, 80% of the 40 SCFM that each will consume, or 32 SCFM, is directed to the cold end. 32 SCFM X 4 3240’s = 128 SCFM. Close enough. They plumbed those 4 Vortex Tubes at approximate equal distances along the length.
*I picked 2psig because that’s the maximum back pressure before it starts to change performance. I also assumed we’re not going to round the entrance of the holes, so I applied the 0.61 multiplier from the table notes.

A Model 3215 Medium Vortex Tube supplied @100psig will flow 10 SCFM worth of cold air when set to a 67% Cold Fraction**, which will give us a curtain of cold air that’s a little more than 71°F colder than the compressed air supply:

**When set to a 70% Cold Fraction (that means 70% of the compressed air supply flow is directed to the cold end), the cold flow from a Vortex Tube supplied @100psig will be 71°F colder than the compressed air supply. At a 67% Cold Fraction, it’ll be a little colder than that.

If you’ve got an application involving the need for cold air, on demand, EXAIR has a variety of products that’ll do just that. Give me a call to find out more.

Russ Bowman, CCASS

Application Engineer
EXAIR Corporation
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What I Do

I’ve blogged before about having a fantastic wife and three smart and rapidly growing daughters. Our nightly routine is one that gets to be cumbersome and sometimes painful, at the same time, I wouldn’t change a single aspect as it gives both my wife and me one on one time with each girl. Even my pre-teen daughter still wants this one-on-one time when we just sit and calm down from the day by talking or singing in her case. I know it won’t last forever, so I always try to stay present. Here lately all three of my daughters on different days have asked me what I do at work during the day. It caught me off guard all three times.

They know that I work for EXAIR, and they know we make “stuff”, they’ve been to the company parties and even had lunch with me here in the office, they still didn’t know what I did, and at the time each one asked, even I didn’t know what I did. The answers I gave were all fairly similar. I help people figure out how to fix stuff by using the stuff we make. If they have something from EXAIR that isn’t working then I help them figure out why it isn’t working, and we try to get it fixed. Then they would ask things like, if their car is broken they call you, no that’s only when I’m at home. I tell them I also get to test products and see what they can do, even make videos of what our stuff does. Of course, they wanted to know if I made TikToks and I proudly informed them I do not and that most of this stuff is on a website or on YouTube.

The fact is that they know I love to work with my hands and see my work around the house or at other people’s homes on their cars or on their projects. They know that I value my experiences and I always try to have them recall an experience they may have already had when they are struggling with something. The best is when my oldest is learning about heat transfer. First, we did an experiment with my trusty Zippo lighter, so she experienced that holding your hand six inches over a flame you can feel the warmth but underneath you can’t. Then I showed them Vortex Tube Videos. They didn’t find it as cool as I do. (DAD PUN INTENDED!)

Lucky for me, when people are contacting me at work, they generally get excited about seeing compressed air turned into hot and cold air streams without moving parts and being able to solve heat transfer issues quickly and easily. The exact opposite reaction of young children, which helps me not feel like such a nerd.

The point of this story is that I am here to help, it’s one of the key responsibilities I hold as an Application Engineer here at EXAIR. With that, I share all of my experience that comes with over 15 years in the industry and always keep my eyes and ears open when I don’t know something. If you are at a wall with your point-of-use compressed air system or a process in your manufacturing, contact us and see how our bank of experience can help you to determine the best path moving forward.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

What OSHA 1910.242(b) Means For Compressed Air Product Users

Medically speaking, our skin is an organ…and an amazing one at that. It protects our internals from an incredibly harsh environment as we’re bombarded by radiation (sunlight), subjected to summer’s heat & the cold of winter, attacked by fierce invaders (from viruses & bacteria to insects & spiders), all while we carry on at the bottom of a 60 mile-deep ocean (of air!)

Our skin requires some protection too: Sunscreen mitigates some of the harmful effects of solar radiation, shoes protect our feet from the ground, gloves & coats prevent frostbite, and compliance with OSHA Standard 1910.242(b) protects operators who use compressed air devices for cleaning purposes from air embolisms. That’s when air, under pressure, has enough energy to break the skin (tough as it is) and reach the tissue underneath. It’s painful, and serious enough that the victim should absolutely seek emergency medical treatment. If the air breaks a blood vessel and enters the pulmonary system, it can be deadly, in a hurry.

In 1971, the U.S. Occupational Health and Safety Administration (OSHA) determined that air under pressure higher than 30 pounds per square inch is capable of causing such injuries, if the pressurized source is dead-ended into the skin. Based on this determination, they included the following verbiage in Standard 1910.242, regulating the safe operation of hand and portable powered tools & equipment:


1910.242(b) Compressed air used for cleaning. Compressed air shall not be used for cleaning purposes except where reduced to less than 30 p.s.i. and then only with effective chip guarding and personal protective equipment.


In February 1972, OSHA issued Instruction STD 01-13-001 to clarify the meaning of 1910.242(b), with two illustrations of acceptable methods to meet compliance. The first is the use of a pressure reducer (or regulator):

While this method is compliant with the OSHA Standard, it’s kind of impractical, since you’re not going to get a whole lot of cleaning done with such a low energy air flow. If that’s not bad enough, it’s STILL going to be loud, and wasteful as far as the cost of compressed air goes.

The other method illustrated in the Instruction’s enclosures involves the nozzles themselves:

Compressed air product manufacturers use this method to make OSHA compliant Nozzles.

One design that complies with OSHA 1910.242(b) using this method is the cross drilled nozzle:

Unless it’s blocked off, practically all of the air flow goes straight out the end, but if you block off the end, it all goes out the cross drilled hole. As long that hole is properly sized, you won’t build up 30 psi at the main outlet.

If you’re not concerned about high operating cost or deafening noise, you can stop reading now; these are all you need for OSHA compliance with Standard 1910.242(b). If you DO care about spending less money on compressed air or complying with OSHA Standard 1910.95(a) (which you read all about here), let’s spend a minute on engineered compressed air nozzles:

EXAIR Super Air Nozzles discharge compressed air through an annular array of holes, recessed between a series of fins. This causes the primary (compressed air) stream to entrain an enormous amount of air from the surrounding environment.

In addition to making them cost less to operate (since most of the total developed air flow is entrained), they’re also VERY quiet (since the entrained air forms a boundary layer on the outside of the air stream), AND they can’t be dead ended:

Since the fins won’t allow for a complete blockage of the compressed air discharging from the Super Air Nozzle, this design is a prime example of a built-in “relief device” as defined by Instruction STD 01-13-001, above.

All EXAIR Intelligent Compressed Air Products, in fact, incorporate a form of built-in “relief device”:

The overhang of the cap on the Flat Super Air Nozzles and the Super Air Knives prevent them from being dead ended.

If you’d like to discuss safe use of compressed air, it’s one of our primary goals here at EXAIR – give me a call.

Russ Bowman, CCASS

Application Engineer
EXAIR LLC
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