Hazardous Locations need Cabinet Cooling too!

Hazardous Locations are a tricky opponent for electrical panels and controls. To safely be in a HAZLOC they either have to be rated for that Environment or they need to be enclosed in a Cabinet that is purged and pressurized to keep any explosive gases, fumes, or dusts out of the Cabinet. This is no new thing, however as the Industrial revolution 4.0 continues to grow and progress products are continually being added to HAZLOC areas. For example, robotic controls, analyzers, motors and switch gears now use electronic accessories to meet the needs for, speed, process control and energy efficiency, which often renders the equipment unsuitable for use in hazardous locations.  While the demand for these new devices continues to grow, not all of these items are able to be made intrinsically safe. And the items that are not will need to be enclosed in a cabinet where heat will build and you need to manage that heat load while retaining the positive pressure a purge and pressurization is putting on the panel.
EXAIR HazLoc Cabinet Cooler Systems are rated for Class I Div 1 & 2, Class II Div 1 & 2, and Class III environments.
First, we need to know what Class, Division, Group and Temp Code your area falls in. Area Classification Methods  The NFPA (National Fire Protection Association) establishes area classifications using three factors. Identified as Classes, Groups and Divisions, these factors are combined to define conditions of specific areas. Class Ratings – Classes are used to define the explosive or ignitable substances that are present in the atmosphere. Class I – Flammable gases or liquid vapor. Class II – Ignitable metal, carbon or organic dusts. Class III – Ignitable fibrous materials. Division Ratings – Divisions are used to define the degree of hazard by determining the explosive or ignitable substance’s expected concentration in the atmosphere. Division 1 – Contains substances under normal conditions Division 2 – Contains substances under abnormal conditions Group RatingsGroups are used to define substances by rating their explosive or ignitable nature, in relation to other known substances. TYPICAL CLASS I SUBSTANCES Group A – Acetylene Group B – Hydrogen or > 30% Hydrogen by Volume Group C – Ethyl Ether & Ethylene Group D – Acetone, Ammonia, Benzene & Gasoline TYPICAL CLASS II SUBSTANCES Group E – Aluminum, Magnesium & Alloys Group F – Carbon, Coke & Coal Group G – Flour, Grain, Wood, Plastic & Chemicals Temperature Class – A Temperature Class is a term that is allocated within a hazardous area or zone to instruments and equipment. The classification or rating signifies the levels of thermal energy allowed in a particular area or produced by specific equipment. EXAIR products are Able to be used in locations at or lower than T3C. EXAIR Cabinet Cooler Systems are available, from stock, to suit most any electric/electronic panel heat protection need:
  • Cooling capacities from 275 to 5,600 Btu/hr. Call me if your heat load is outside this range…we can look at customized solutions too.
  • NEMA 12 (IP54), 4, or 4X (IP66) ratings.
  • Thermostat Control – Standard, or Electronic Temperature Control.
  • Non-Hazardous Purge for contaminant exclusion on less-than-ideally sealed enclosures.
  • High Temperature models for ambient temperatures from 125°F (52°C) to 200°F (93°C).
  • Side Mount Kits when space is limited above the panel.
  • 316SS construction for particularly aggressive environments.
  • UL Classified for hazardous locations,
    • Class 1 Div 1, Groups A,B,C and D
    • Class 2 Div 1, Groups E,F, and G
    • Class 3
    • Temp T3C
When choosing products for use in classified areas, it’s critical to ensure safety through compliance, and the HazLoc Cabinet Cooler Systems allow you to do that, with simplicity and reliability.  If you’d like to discuss an enclosure cooling application, in or out of a classified area, give us a call. Jordan Shouse Application Engineer Send me an Email Find us on the Web  Like us on Facebook Twitter: @EXAIR_JS

Super Air Wipes can Help to Protect a Camera Lens

2403SS

An oil and gas company was using a camera to watch a drilling rig.  During the operation, water and mud could be slung toward the camera lens, and create spots.  An operator would have to leave their position to clean the lens.  Since they were looking for a way to force the water and mud away from the lens, but it had to be clear.  Since air is transparent, they contacted EXAIR for our expertise. 

As an air barrier, customers have used the Super Air Knives to separate material/heat/gases from different areas in similar applications.   But, for this customer, they were interested in the Super Air Wipe; and at EXAIR, we state that there is more than one way to solve a riddle.  With the speed of the water and mud, I was not keen on the ability of how well the Super Air Wipe could work.  So, I decided to test it. 

At EXAIR, we offer customers the option for us to test our products in different applications.  This could also include testing your items with our products.  EXAIR offers an Application Assistance form to help get this started.  If we have the capabilities, we can setup a “mock” system to test and verify, and we can shoot a short video to present the information to you.  This can include conveyance testing, product comparisons, cleaning, cooling; and, for the customer above, air barrier testing. 

Their current operation was using a wiper to clean the glass.  Like with any wiper, material can get wedged under the wiper and cause streaks, and it could scratch the glass lens.  To stop replacing the wiper blade or in some instances, the glass lens; they were looking for a non-contact way to keep the water, sand, mud from the camera lens.  Since it was difficult for them to determine the velocity of the material that would be heading toward the camera, they requested that I use water for my test.  With a 1/4” (6 mm) O.D. tubing, they believed that it could represent a good velocity with a pressure of 20 PSIG (1.4 Bar) and a flow of 30 GPH (113.6 LPH).  This would create a velocity of 9.3 mph (15 kph).  Since the lens had a diameter of 2” (51mm), I recommended the model 2403SS, 3” Stainless Steel Super Air Wipe.  Here is a video of the results with the inlet air pressure at 80 PSIG (5.5 Bar).

Water Test

To expand a bit more on the Super Air Wipe, it is designed to blow compressed air in a 360-degree flow pattern.  This air pattern is directed at a 30-degree angle toward the center to blow the debris back away from the camera lens, just like a cone.  The Coanda effect maximizes the entrainment of ambient air into the compressed air.  This makes the unit very efficient and very powerful.  The model 2403SS Super Air Wipe has an I.D. of 3” (76 mm) which gives it enough clearance away from the view of the camera.  It is constructed of 303 stainless steel construction for corrosion resistance with a stainless-steel braided hose that connects the two halves together.  The design is very rugged for outdoor use. 

At EXAIR, we offer a 30-day unconditional guarantee on our stock products for US and Canadian customers to try things out.  But sometimes this may not be enough.  For the customer above, we were able to try something different to verify the effectiveness in keeping the camera lens clean.  And at EXAIR, we will take that extra step to help our customers.  If you have a pneumatic application that requires some additional service, you can fill out the Application Assistance form or contact an Application Engineer.  We will be happy to help you, and perhaps we can put some “focus” on a solution. 

John Ball
Application Engineer

Email: johnball@exair.com
Twitter: @EXAIR_jb

HazLoc Cabinet Cooler Systems: Application for Gas Sampling

A company from the Middle East contacted me about cooling a gas sampling device that was placed inside an enclosure.  The Middle East is well-known for Oil and Gas and hot ambient temperatures.  The sampling system was used by a Petroleum company to measure the composition of gas samples.  This type of device had a refrigerant system to keep the sample at a predetermined temperature.  Since the ambient conditions were very high, they noticed incorrect readings with their calibration gas.  They wanted to use an enclosure to protect the instrument from the environment and to use the Vortex technology to cool the surroundings of the gas sampling instrument to help it work properly. 

Like with any A/C unit, the higher ambient temperatures will reduce the cooling capacity of a refrigeration system.  The customer gave some details of what they needed.  They wanted to target an internal temperature at a maximum of 35oC (95oF) which would allow for proper readings.  The enclosure measured 2000 mm X 1200 mm X 1000 mm (79” X 47” X 39”), and it was made from 316SS with insulation inside.  The area was classified as a Class 1 – Div2 which means that there is a potential for an explosive gas to be present.  The sampling machine generated about 170 watts (580 BTU/hr) of heat inside.  The maximum ambient temperature was 50oC, and the instrument grade air that was being used for the Cabinet Cooler was only at 6 bar (87 PSIG).  With all this information, I had a lot to consider to determine the correct cooling capacity.

The first thing that I needed to decide was if they had a purge system on the hazardous panel.  They sent a diagram setup of the panel as shown below.  They did have a Z-purge system as reference as #4 in the diagram.  (This was the correct type of purge system for a Div2 area).  They also showed a check valve on the cold air side to reduce the potential risk for ingress.  With the design of the EXAIR HazLoc Cabinet Coolers, we use a poppet valve to keep any dangerous liquids or gases from entering.  So, they could remove it from their item list which saved them money.    

With the calculation for the total heat load, I recommended the model HZ4840SS-316-240.  When they installed the EXAIR system to their enclosure; they were extremely happy with the compact size and the ease of installation.  Now, when a sample bottle came in for test, they were able to attach it to the gas sampler and allow for the Z-Purge system to evacuate the enclosure.  Once the purge system cycled, the solenoid valve for the Cabinet Cooler as well as the gas sampling system started operating.  With the instant cold from the HazLoc Cabinet Cooler, the gas sampling equipment was able to find the composition of the gas accurately and consistently. 

The EXAIR HazLoc Cabinet Cooler Systems are designed to keep your electrical panels cool within hazardous areas like the Class I – Div 2 above.  The certification is under UL Classified for Class I, Class II, and Class III areas with both Div1 and Div2.  System shutdowns from electrical components overheating or incorrect measurements with gas sample analysis are costly and potentially dangerous.  If you would like to discuss in more details about the different types of EXAIR HazLoc Cabinet Coolers, an Application Engineer at EXAIR will be happy to help you. 

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb