The Technology of Cooling Part 3: Cooling with Closed Loop Cooling Units


Pfannenberg cooling units operate on the principle of the Carnot cycle. This means that the cooling units function as a heat pump that “pumps” the thermal energy transferred from the electronic cabinet (heat dissipated from the components) up to a higher level of temperature (the ambient temperature can reach levels as high as + 55 °C). The air inside the enclosure is cooled down by the evaporator and at the same time dehumidified.

How do I know if a cooling unit is the right product for my application?

  • If the ambient temperature is greater than the target internal temperature of the enclosure, active cooling is required.
  • If indoor NEMA Type 12 applications, NEMA Type 3R/4 outdoor applications and NEMA Type 4/4x stainless steel for washdown applications are required – closed loop cooling can maintain the NEMA Type rating of the cabinet.

Properly sizing a cooling unit

To properly size your cooling units you must know the required cooling capacity in Watts, mounting requirements (side, integrated or top mount) and the dimensions of the cooling unit and enclosure.

Utilizing performance curves to properly size cooling units:

> Pfannenberg utilizes the DIN standard 35/35 °C when rating our cooling units.

> Many other companies use 50/50 °C, which provides a higher, non-usable value. Customers should use their own application temperatures to determine the proper cooling capacity of the system.

 

 

 


Important information when utilizing cooling units:

  • The refrigeration capacity should exceed the dissipation loss from the installed components by approximately 10%.
  • The enclosure should be sealed to prevent the inflow of ambient air.
  • Use the door contact switch to impede operation with open doors and consequent excessive accumulation of condensation.
  • Use cooling units with maximum clearance between air inflow and air outflow to prevent poor circulation.
  • Make sure that the air inflow and air outflow in the external circuit is not hindered, preventing proper heat exchanging at the condenser.
  • When using top-mounted cooling units, make sure that components with their own fans do not expel the air directly into the cooling units cool air outflow.
  • Make sure unit is level.
  • Setting the temperature to the lowest setting is not the optimal solution due to the condensation issues. The value we have preset on the cooling unit is a sound compromise between cooling the inside of the enclosure and the accumulation of condensation.

In harsh environments involving high temperatures, wash-down requirements, heavy particulate matter or the presence of chemicals capable of damaging components (NEMA 4 or 12 environments), ambient air must be kept out of the enclosure. Pfannenberg Cooling Units seals out the ambient air, cooling and re-circulating clean, cool air throughout the enclosure.

Pfannenberg offers Critical Thermal Management Solutions for Maximum uptime and efficiency.

Find the previous articles of this “Technology of Cooling” serie: Cooling with Filterfans® and Cooling with Closed Loop Air to Air Heat Exchangers.

Read the last part of this “Technology of Cooling” serie: Closed Loop Liquid Cooling Solutions

 

Topics: Enclosure CoolingCooling UnitsThermal Management

The Technology of Cooling Part 2: Cooling with Closed Loop Air to Air Heat Exchangers


Closed Loop Cooling and particularly Air to air heat exchangers are used when the complete separation between the enclosure and the environment is required and the internal enclosure temperature to be cooled can be higher than the ambient. The air to air units have a rating showing how much heat can be removed based on the difference in the ambient and the internal temperatures. This is traditionally rated on W/°C which is the watts of heat that the unit can remove per temperature difference in °C.

How do I know if an air to air heat exchanger is the right product for my application?

  • If the ambient temperature is lower than the desired temperature inside the enclosure.
  • If a total separation between ambient air and enclosure air is required.

Properly sizing an air to air heat exchanger

To properly size an air to air heat exchanger you must know the required cooling capacity in Watts, target temperature rise over ambient and the dimensions of the heat exchanger and enclosure.


Utilizing performance curves to properly size air/air heat exchangers:

> Pfannenberg utilizes watts of heat that the unit can remove per temperature difference in °C.

Customers should use their own application temperatures to determine the proper cooling capacity of the system.


PAI_drawing.jpg

Important information when utilizing air/air heat exchangers:

  • The max ambient is 35 °C (95 °F) and the max internal temperature that the system can take is 45 °C (113 °F).
  • Can be used when the temperature difference is 10 °C.
  • If you apply this temperature difference to the rating of the air to air unit you will get the total amount of heat that can be removed.
  • A unit rated 100 W/°C could remove 1000 Watts (100 x 10) of heat under these conditions.

Closed Loop Cooling with air to air heat exchangers is the most efficient cooling solution as cooling with ambient air is the most economical type of cooling!

Pfannenberg εCOOL Air to air Heat Exchangers feature an energy efficient, minimal maintenance design. Installation and maintenance of these units requires much less time compared to other closed loop Thermal Management solutions.

Click here to read the 1st part of this “Technology of Cooling” serie: Cooling with Filterfans®
Click here to read the 3rd part of this “Technology of Cooling” serie: Cooling with Closed Loop Cooling Units

Topics: Enclosure CoolingCooling UnitsThermal Management

Download Pfannenberg’s NEW 2016 Thermal Management Catalog!


We are excited to announce the release of our NEW NORTH AMERICAN CATALOG. In this catalog we take a Solutions First approach to helping you understand how to choose the best Thermal Management products for your applications.


> New sections for Engineered Solutions and Industry Group Specific Solutions.
> Shared expertise to find the best solution for any type of application and environment.
> Easily determine the correct thermal management products for your application and environment.
> New high resolution detailed product pictures with cut-aways.

 

Get Pfannenberg Catalog


Pfannenberg, Inc. is a global manufacturer of thermal management, water cooling solutions and signaling technology. For more than 60 years, our enclosure cooling products have been helping some of the largest companies worldwide stay cool and safe, protecting and keeping electronic equipment running to avoid costly downtime.

In addition to our thermal management products we also manufacture visual and audible signaling devices for security, industrial fire, building, industrial process, disaster warning, hazardous areas, light art and illumination. Our business philosophy – Protecting man, machine and the environment.

To learn more about how we can help you, contact us today! We have a wide range of expertise to share with you.

 

Topics: Enclosure CoolingThermal ManagementNorth America

The Technology of Cooling Part 1: Cooling with Filterfans®


If the installation is in a clean, non-hazardous environment with an acceptable ambient (outside the enclosure) temperature range, a simple forced-air cooling system utilizing outside air is usually adequate. Combined with an air filter, such devices generally meet the heat removal needs of typical electronic equipment and many electrical applications. 


How do I know if a Filterfan® is the right product for my application?

  • If the temperature rise inside the enclosure can be higher than the ambient
  • If multiple configurations are needed. Filterfans® can be located in a number of locations within complex enclosure configurations.

Calculating the required airflow

To properly size a Filterfan® it’s important to understand how static pressure effects the performance of a fan.


Understanding CFM

CMF describes the volume flow rate of compressed air. We can define 3 different CFM:

  • CFM1: Fan Only (unfiltered)
  • CFM2: Filterfan® Assembly (uninstalled)
  • CFM3: Filterfan® Installed on an enclosure with one filtered exhaust assembly
    (Note: Always calculate cooling capacity of Filterfans® with the CFM3 value)


Utilizing Filterfans® for Enclosure Cooling 

  • Always use the Filterfans® to propel the cool ambient air into enclosure.
  • Slight positive pressure builds up inside the cabinet so that only air filtered by the Filterfans® flows into the enclosure.
  • The air propelled into the cabinet displaces the warm air which exits through the exhaust filter.
  • When installing a combination of Filterfans® and exhaust filters, fit the Filterfans® in the lower third of the cabinet and the exhaust filter(s) near the top of the cabinet.

Utilization examples

CFM : Filterfan® + Exhaust Filter CFM : Filterfan® + 2 Exhaust Filters CFM : Filterfan® + intake + Filterfan® Exhaust

 

Part 1 of our Thermal Management Solutions, Pfannenberg’s Filterfans® incorporate modern louvers which enable maximal airflow, hold back dust/flour and water particles, protect the filter medium from damage and can be integrated into the design of the application. Filterfans are an ideal cooling solution when the ambient air is always lower than the temperature required in the electrical enclosure. This assists the natural convection of the air and avoids hot spots withing the enclosure.

Pfannenberg is the inventor of the Filterfan®, with 50 years of experience and continuous development. Trust in the Original


Read the 2nd part of our Thermal Management Tips: Cooling with Closed Loop Air to Air Heat Exchangers

Topics: FilterfansEnclosure CoolingThermal Management

Liquid Cooling Solutions, the Best Choice for Complete Plant-wide Machine Cooling


When it comes to Thermal Management, cooling each machinery or electrical cabinet separately is usually the solution chosen by most of the industries. However, this leave a valuable optimization potential untapped.

Maximum efficiency cooling for a whole system can be achieved with a cooling system solution consisting of air to water heat exchangers and water-based chillers. These ‘Liquid Solutions’ cool the complete assembly and offer significant benefits compared to traditional approaches such as cooling with ambient air.

How does it work?

A closed loop cooling or semi open system is used to provide cooling to the entire plant assembly. These might be electrical enclosures, processes or individual machine parts such as spindles, motors or hydraulic equipment.

Liquid Cooling Solutions

In a closed-loop system, electrical enclosures or assemblies are cooled with cold water at a specified inlet temperature which is pumped through a pipe system. Flowing through the electrical enclosures or assemblies, the water is warmer when it returns to the chiller. This creates a temperature delta which the chiller equalizes by cooling the water from the outlet temperature down to the inlet temperature.

The process chiller system feeds cold water into the application inside the factory hall or outdoors and the constant flow temperature significantly improves machine availability and machining accuracy. There is no other cooling media being as efficient as water cooling.

The best Liquid Cooling Solution: Combined Chillers and Air to Water Heat Exchangers

The combination of application-specific process chillers with air to water heat exchangers is particularly suitable for applications in which heat must not be dissipated in the immediate environment, where the ambient air is too aggressive to allow the use of traditional enclosure cooling units, where high-level protection is required (up to IP 65) or where the cooling devices must be maintenance-free.

The air to water heat exchanges are all cut-out-compatible and fit in the housing of all available electrical enclosures. This means that machine and plant manufacturers, end users and distributors benefit from higher flexibility, and save costs on warehousing and servicing.

The advantage of an intelligent system solution with application-specific chillers and air to water heat exchangers is that the dissipated heat can be moved directly from the factory shop floor via air channels or an outside chiller system. It also offers very high reliability and problem-free operation as all the components of the system are chosen to work together perfectly. Low maintenance, cut-out-compatibility and energy efficiency optimize energy consumption and keep operating costs to a minimum. The integrated concept and numerous options allow the system to be adapted to almost any application, even with changing conditions.

Application-specific configuration

Pfannenberg’s experts work with their customers to develop application-specific chiller systems. To achieve exactly the right configuration, it is essential to:

  1.  First determine the heat load for the whole assembly.
  2. The second step is to specify the type of cooling medium (ideally water), the target temperature and the flow quantity which the system must deliver in the actual application. This process should take into account how the heat is transmitted to the cooling medium and the type of refrigerant necessary to operate the refrigerant circuit. The type of cooling medium and which chiller model is used depends on whether usable process water is available at the factory and if so, whether it is warm or cold (see overview of device variants).
  3. An analysis of the environmental conditions prevailing where the chiller system is to be installed is also carried out. For example, there might be high temperatures and contaminated air indoors, while outdoors the temperature might fluctuate widely. Both of these factors can have an impact on the configuration of the chiller system, making accessories such as filter fans or crankcase heating necessary. Taking the temperature of the cooling medium at the inlet and the highest likely ambient temperature as a basis, Pfannenberg determines the best chiller model with the correct characteristic curves for the job.
  4. The final stage in the application-specific configuration is to think about whether the selected standard version meets the other requirements of the application, such as performance data, control and regulation options, available space, certifications and color. It is then decided whether standard options are necessary or helpful and if so, which. With numerous available options available, the EB chillers meet the requirements of practically any application in industrial environments.

Pfannenberg offers installation-ready chiller systems with performance specifications ranging from 1 to 160 kW. The modular concept of the EB series allows users to select from up to 30 standard options. These include hydraulic bypass/relief valves, flow monitors, tank level monitors, air filters, air filter monitors, check valves, solenoid valves, single alarm display and UL certification. Special solutions are also available. Click here to determine the correct chiller for your application!


With products that include filterfans, heaters, industrial air conditioners, air to water heat exchangers, packaged chillers, and signaling devices, Pfannenberg offers a full range of thermal management solutions for all types of industries. Standard options such as stainless steel materials, NEMA 4/4X enclosures, and washdown duty construction allow these time-tested products to be seamlessly incorporated into even the most demanding applications.

Have a question regarding which equipment is best for your application? Ask Us Here.

Topics: Air Water Heat ExchangersEnclosure CoolingThermal ManagementWater Cooling,Packaged ChillersChillers

Cooling Food & Beverage Applications with Pfannenberg’s DTS/DTT Series

Innovative, Efficient, Reliable

Whether in washdown locations or control rooms, the DTS Series key internal electronics are positioned away from potentially moist and/or caustic air in food and beverage applications.  The wide condenser fin spacing allows for filterless and maintenance-free operation.  The stainless steel units have an epoxy coating on all exposed copper tubing to compliment the electrostatically-coated condensers. The fans are conformal coated, backward curve impellers that have a standard life of 55,000+ hours, providing the longest life and best air flow in their class.

DTS Series Cooling Units

  • Active condensate management utilizes a PTC heater which eliminates the need for drain line.
  • NEMA Type 4/4X 304 Stainless Steel with #3 polish to repel contaminants in food grade applications and to provide for easy washdown.
  • High Temperature models can operate in ambient temperature models can operate in ambient temperatures up to 140° F (60° C), ideal near industrial ovens or baking lines.
  • Optional cover to protect fan if used in washdown or in high dust/debris areas.

DTT Series Top Mount Cooling Units

  • DTT Series Units provide convenient top mount cooling while eliminating the danger of condensate entering cabinets.
  • Innovative service panel design provides easy to change filters, controls and fuses, decreasing service time and allowing filters to be changed without downtime.
  • Product variety: multiple performance levels available.
  • Easy mounting: quick release mounting frame and quick mount design.

By keeping electronics in enclosures from overheating, Pfannenberg provides an invaluable service to companies, keeping their machinery and processes consistently operating.  By developing and producing products which are designed to save energy and other resources, Pfannenberg operates by their business philosophy – Protecting man, machine and the environment


Topics: Enclosure CoolingCooling UnitsThermal ManagementNorth AmericaFood & Beverage

Pfannenberg Food & Beverage Applications: Air/Water Heat Exchangers

The Complete Liquid-Cooled Solution for F&B Industrial Control Enclosures

For over 50 years Pfannenberg has been a leader in thermal management solutions.  From simple Fan Cooling and Packaged Air Conditioners to more complex water cooled applications, our expertise helps ensure industrial electronics operate at peak efficiency and extended service life.

Pfannenberg’s Air/Water Heat Exchangers offer a solutions to fix your thermal management problems in washdown areas of the plant or areas with high amounts of particulate . The sealed cabinet provides contaminant-free component cooling without adding heat to the local environment.  It provides an excellent economic solution where plant water is available or when used in conjunction with a process chiller.  It’s sealed design and available stainless steel, NEMA Type 4/4X construction provides a maintenance free solution with no exposed fans or maintenance of filters required.

Typical Food and Beverage Applications:

  • Ingredient Mixers
  • Product Cooling/Drying
  • Packaging Automation Equipment
  • Inspection Machines
  • Oven Controls

For applications which require local enclosure cooling using a remotely located source of refrigeration, PWS Series Air/Water Heat Exchangers provide the perfect solution.  Paired with our CC or  EB Series Chillers, the air/water heat exchanger provides a total cooling solution that manages process and/or control enclosure heat gain and effectively removes it from the processing area.  Single source responsibility for the complete system ensures properly matched components that are engineered to work together – and to provide a custom fit to the most complex food processing equipment.


Topics: Air Water Heat ExchangersEnclosure CoolingCooling UnitsThermal ManagementNorth AmericaWater CoolingPackaged ChillersFood & Beverage

Liquid Cooling Solutions for Commercial Bakery Electrical Enclosures


Are the VFDs in your Commercial Bakery failing due to high amounts of flour and moisture entering your electrical enclosure?

Pfannenberg is your proven partner for complex thermal management problems in the baking industry. High security classes of equipment and corrosion-resistant construction materials resist even the most difficult ambient conditions.

Looking for another energy savings solution? Pfannenberg’s PWS Air/Water Heat Exchangers are ideal for cooling your electrical components. Designed for maintenance free operation in the most demanding areas of a plant.

Click here to download the NEW Pfannenberg Bakery Flyer!

Also, be sure to visit us at IBIE 2016 in Las Vegas, NV — October 8th-11th at Booth #9247!

Topics: Air Water Heat ExchangersEnclosure CoolingCooling UnitsThermal ManagementNorth AmericaWater CoolingFood & Beverage

The Advantages of Air To Water Heat Exchangers for Thermal Management in Harsh Environments


Money-saving approach yields longer service life while conserving energy.

Control Panel Cooling Technique Helps Mitigate Hydrogen Sulfide Corrosion Problems with Wastewater Pumping Systems

Air To Water Heat Exchangers provide an energy efficient and reduced manintenance method for cooling electrical control panels.

Enclosure Cooling Units offer a straightforward active-cooling technique for pump control panels, however, they are not necessarily the best choice for all installation locations. Dirt, dust, and other airborne contaminants can clog condenser coils; while corrosive gasses in the environment can lead to premature failures.On the other hand, Air To Water Heat Exchangers can satisfy the same requirements without circulating ambient air within the housing, thereby eliminating the clogging and corrosion problems associated with airborne contamination.

A common threat to organic wastewater handling and treatment systems is the presence of hydrogen sulfide gas. Not only is this gas toxic to humans, but it also contributes heavily to corrosion problems in pipes, structures, instrumentation, and electrical systems. Lift stations and pumping systems are particularly vulnerable as H2S sour gas readily attacks copper used in wires, electrical contacts, and cooling units used on motor control centers (MCC’s).

Electronics cooling is vital for MCC’s containing the variable frequency drives (VFD’s) that are used to maintain efficient operation by conserving energy through regulating the speed at which pumps operate. Since VFD’s generate a considerable amount of heat, it is necessary to employ an active enclosure cooling technique in order to keep VFD’s operating within acceptable temperature limits. The absence of effective cooling will quickly allow VFD’s to overheat, shut down, or even catastrophically fail. In addition to being an economic loss, such outages disrupt production and affect the efficiency of plant operations.

Effective electrical enclosure cooling for environments where H2S gas is present must utilize a closed loop technique to ensure that sour gas is not introduced into the enclosure where it could harm wiring, electrical connections, switches, and other components. In fact, for many installations it is advantageous to deploy an air or nitrogen purge system which creates a positive pressure within the enclosure in order to keep undesirable ambient elements, including sour gas, outside of it. As opposed to an open loop system that uses fans to draw ambient air into and push heat out of the enclosure, a closed loop system maintains isolation of the ambient air and permits the NEMA rating of the electrical enclosure to be maintained. Examples of closed loop cooling equipment for electrical enclosures include cooling units (also known as enclosure air conditioners or enclosure AC) and Air To Water Heat Exchangers.

Cooling units offer the advantage of a being a plug and play solution – they simply hang onto the outside of the enclosure and are connected to power already available inside the enclosure. However, these compressor-based refrigeration systems consume a fair amount of energy and require periodic maintenance. Additionally, to endure the sour gas environment, exposed copper pipes and condenser coils must be treated with a conformal coating – which is not necessarily standard. Over time, the need to clean condenser coils – which may require partial disassembly of the cabinet – can lead to scratched paint, compromised coatings, and eventual corrosion.

Air-to-water Heat Exchangers offer several advantages making them the preferred method for closed-loop, electrical enclosure cooling. Acquisition and operating expenses are significantly lower than those of a compressor-based cooling unit.

Additionally, this product is virtually maintenance free and since there is no ambient air circulation within the unit, there is no risk of H2S sour gas corrosion to internal components.

There are, however, two challenges with acquiring and implementing these units:

  • The units must be specified as the solution of choice with the MCC or pump system integrator.
  • The units must be connected to a viable source of clean water or coolant to circulate through the heat exchanger coil.

Another viable implementation is to consider retrofitting cooling units with air-to-water heat exchangers. This modification can be readily accomplished without difficulty since some units share the same enclosure cut-out. For dissimilar cutouts, an adaptor plate may be required to reduce the size of the opening.

Click here to download the Case study in PDF

Need more information on Pfannenberg’s PWS Air to Water Heat Exchangers? Click here and discover all the advantages of this product!


Topics: Air Water Heat ExchangersEnclosure CoolingThermal ManagementWater CoolingWater TreatmentWastewater Treatment

The Technology of Cooling: Cooling with Closed Loop Cooling Units


Pfannenberg Cooling Units operate on the principle of the Carnot cycle. This means that the cooling unit functions as a heat pump that “pumps” the thermal energy transferred from the electronic cabinet (heat dissipated from the components) up to a higher level of temperature (the ambient temperature can reach levels as high as + 55 °C). The air inside the enclosure is cooled down by the evaporator and at the same time dehumidified.

How do I know if a cooling unit is the right product for my application?

> If the ambient temperature is greater than the target internal temperature of the enclosure, active cooling is required.
> If a NEMA Type 12 to 4x rating is required – closed loop systems can maintain the NEMA Type rating of the cabinet.

Properly sizing a cooling unit:

To properly size a cooling unit you must know the required cooling capacity in Watts, mounting requirements (side, integrated or top mount) and the dimensions of the unit and enclosure.

{PC = PD – PR }
> Pc [ Watt ]: Refrigeration capacity of a cooling unit.
> PD [ Watt ]: Dissipation Loss: Thermal power generated inside a cabinet by the dissipation loss of components.
> PR [ Watt ]: Radiant heat gain/loss: Heat transfer through the skin of the enclosure (insulation factor not included).

{PR = C x A x ∆T }
> C [  W/m2 °C ]: Coefficient of heat transmission.
> A [  M2 ]: Surface area of electronics cabinet.
> ∆T [ °C ]: Difference in temperature between the ambient air and the air inside the electronics cabinet.

Utilizing performance curves to properly size cooling units:

Pfannenberg utilizes the DIN standard 35/35 °C when rating our cooling units. Many other companies use 50/50 °C, which provides a higher, non-usable value.

Customers should use their own application temperatures to determine the proper cooling capacity of the system.

To properly size your Cooling Units you can also use Pfannenberg’s PSS Software which will guide you through the sizing process, to calculate the correct product for your application.


Important information when utilizing cooling units:

  • The refrigeration capacity should exceed the dissipation loss from the installed components by approximately 10%.
  • The enclosure should be sealed to prevent the inflow of ambient air.
  • Use the door contact switch to impede operation with open doors and consequent excessive accumulation of condensation.
  • Use cooling units with maximum clearance between air inflow and air outflow to prevent poor circulation.
  • Make sure that the air inflow and air outflow in the external circuit is not hindered, preventing proper heat exchanging at the condenser.
  • When using top-mounted cooling units, make sure that components with their own fans do not expel the air directly into the cooling unit‘s cool air outflow.
  • Make sure unit is level.
  • Setting the temperature to the lowest setting is not the optimal solution due to the condensation issues. The value we have preset on the cooling unit is a sound compromise between cooling the inside of the enclosure and the accumulation of condensation.

Click here to discover our complete range of Cooling Units!

Topics: Enclosure CoolingCooling UnitsThermal Management