Cabinet Enclosure Coolers

PRODUCT OVERVIEW

The Frigid-X series Cabinet Enclosure Cooler for electronic control panels provide a low cost method of both purging and cooling electrical and electronic control panels by using a stainless steel vortex tube to create cold air from ordinary compressed air.

Our Cabinet Enclosure Coolers are compact and can be installed in minutes through a standard electrical knockout.

Nex Flow™ Offers  4 Types of UL Listed NEMA Rated Electrical Panel Coolers:

Frigid-X Cabinet Panel Coolers NEMA Type 12 (IP-52) For Electronic Control Panels for General use in industrial environments where no direct liquid spray is applied to the unit. Stainless steel construction to hold up in corrosive environments.

Frigid-X Cabinet Panel Coolers NEMA Type 3R (IP-14) For Electronic Control Panels for Outdoor Use. Stainless steel to hold up to rain, snow, humidity and general outdoor use.

Frigid-X Panel Coolers NEMA Type 4-4X (IP-66) For Electronic Control Panels – splash resistant, for use in washdown environments as well as outdoor use. Unique patented design * for secure water tight protection. Stainless steel for food service and corrosive environments. Stainless steel also provides for long life in wet environments and for outdoor use.

Frigid-X Panel Coolers NEMA Type 4-4X-316L (IP-66) For Electronic Control Panels – all external exposed surfaces are of 316L and ideal for pharmaceutical industry and extreme corrosive environments where 303/304 stainless steel is not adequate. As with the NEMA Type 4-4x units, the cooler is splash resistant, for use in wash down environments as well as outdoor use. Unique patented design* for secure water tight protection. 316L Stainless steel for pharmaceutical grade, food service and extreme corrosive environments. Stainless steel also provides for long life in wet environment.

 

* US patent number 8,616,010 / Other  countries: Patented or Patent Pending

Note: Always question non-approved units used on electrical enclosures to assure that your panels are not damaged by inferior products.

 

 

Nex Flow™ offers a High Temperature Warning Sticker free with every Frigid-X Panel Cooler  purchased for the air conditioning of electrical and electronic control panels.  High temperature inside a control panel can be damaging to internal equipment and lead to unplanned shutdown of factory operations.  The label provides for an effective  warning with a color change indicator to ORANGE and a danger warning with  a color change indicator to RED.  Color change is reversible so when the temperature problem is corrected, the label can continue to be used indefinitely.  While it is a qualitative measurement only, it provides an ideal cautionary monitoring of possible temperature problems within a control panel.

Features

  • Low in cost
  • Compact
  • No CFC’s
  • Fast installation
  • Stabilize enclosure temperature and humidity
  • Virtually maintenance free (No Moving Parts)
  • Mounts in a standard electrical knockout
  • Stops heat damage and nuisance tripping
  • Eliminates fans and filters
  • Prevents dirt contamination by keeping enclosure at positive pressure
  • Units applicable to all environments including high temperature to 200ºF

VIDEOS

DIMENSIONS

Contact Nex Flow™ for assistance in sizing cabinet enclosure cooler – Frigid-X series. See Below for Sizing Specifications

MODEL NO. VERSION BTU/Hr. cooling*
(WATTS)
61004A NEMA Type 12 (IP-52) Continuous Operation 290
(85)
61008A NEMA Type 12 (IP-52) Continuous Operation 580
(170)
61015A NEMA Type 12 (IP-52) Continuous Operation 1100
(322)
61025A NEMA Type 12 (IP-52) Continuous Operation 1800
(527)
61030A NEMA Type 12 (IP-52) Continuous Operation 2100
(615)
61040A NEMA Type 12 (IP-52) Continuous Operation 2900
(849)
63004A NEMA Type 12 (IP52) Continuous Operation 290
(85)
63008A NEMA Type 12 (IP-52) on-off control 580
(170)
63015A NEMA Type 12 (IP-52) on-off control 1100
(322)
63025A NEMA Type 12 (IP-52) on-off control 1800
(527)
63030A NEMA Type 12 (IP-52) on-off control 2100
(615)
63040A NEMA Type 12 (IP-52) on-off control 2900
(849)
61004R NEMA Type 3R (IP14) Continuous Operation 290
(85)
61008R NEMA Type 3R (IP-14) Continuous Operation 580
(170)
61015R NEMA Type 3R (IP-14) Continuous Operation 1100
(322)
61025R NEMA Type 3R (IP-14) Continuous Operation 1800
(527)
61030R NEMA Type 3R (IP-14) Continuous Operation 2100
(615)
61040R NEMA Type 3R (IP-14) Continuous Operation 2900
(849)
63004R NEMA Type 3R (IP-14) on-off control 290
(85)
63008R NEMA Type 3R (IP-14) on-off control 580
(170))
63015R NEMA Type 3R (IP-14) on-off control 1100
(322)
63025R NEMA Type 3R (IP-14) on-off control 21800
(527)
63030R NEMA Type 3R (IP-14) on-off control 2100
(615)
63040R NEMA Type 3R (IP-14) on-off control 2900
(849)
61104X NEMA Type 4-4X (IP-66) Continuous Operation 290
(85)
61108X NEMA Type 4-4X (IP-66) Continuous Operation 580
(170)
61115X NEMA Type 4-4X (IP-66) Continuous Operation 1100
(322)
61125X NEMA Type 4-4X (IP-66) Continuous Operation 1800
(527)
61130X NEMA Type 4-4X (IP-66) Continuous Operation 2100
(615)
61140X NEMA Type 4-4X (IP-66) Continuous Operation 2900
(849)
63104X NEMA type 4-4X (IP-66) on-off conttrol 290
(85)
63108X NEMA Type 4-4X (IP-66) on-off control 580
(170))
63115X NEMA Type 4-4X (IP-66) on-off control 1100
(322)
63125X NEMA Type 4-4X (IP-66) on-off control 21800
(527)
63130X NEMA Type 4-4X (IP-66) on-off control 2100
(615)
63140X NEMA Type 4-4X (IP-66) on-off control 2900
(849)
60115X-316L 316 L Stainless Steel NEMA Type 4-4X (IP-66) on-off control (customer supplies own filter)** 1100
(322)
60125X-316L 316 L Stainless Steel NEMA Type 4-4X (IP-66) on-off control (customer supplies own filter)** 21800
(527)
60130X-316L 316 L Stainless Steel NEMA Type 4-4X (IP-66) on-off control (customer supplies own filter)** 2100
(615)
60140X-316L 316 L Stainless Steel NEMA Type 4-4X (IP-66) on-off control (customer supplies own filter)** 2900
(849)

 

** In 316 environments normally customers will have special filtration systems for such environments already.

 

*Cooling effect based on 95°F temperature inside cabinet, 100 PSIG (6.9 BAR) compressor inlet pressure, and 70ºF (21ºC) inlet temperature.

BTU/hr. figures rounded to nearest 100 BTU/hr (1 WATT).

All Continuous Operation models include the cooling unit, filter with auto drain and cold air distribution kit.

All On-Off control units include the cooling unit, filter with auto drain, cold air distribution kit, solenoid valve and thermostat.

SELECTION

Panel Coolers, Panel Cooler, Panel Air Conditioner, Cabinet Enclosure Cooler, Electrical Panel Air Conditioners, Cabinet Cooling Solution, Cooler Master Cabinet, Panel Air Conditioner, Adjustable Thermostat, Electrical Panel Coolers, How to Cool Electrical Enclosures, Electronic Temperature ControlCabinet enclosure coolers come with a 5 micron filter with an automatic drain (except for the 316L stainless steel units) for the compressed air supply to insure clean, dry air and an air distribution kit to circulate the cold air inside the enclosure for even cooling.

Cabinet enclosure coolers are available with or without thermostat control.

When constant cooling and a constant positive purge is required we recommend the continuous operating version without the thermostat and solenoid valve. The cooling effect can be controlled by adding a regulator in line to reduce pressure for reduced cooling when it is not required and to conserve energy.

Systems utilizing a thermostat and solenoid valve saves air by activating the air conditioner only when the internal temperature reaches a critical level. The adjustable thermostat is factory set at 95°F but can be readjusted on site.

Thermostat and solenoid valve systems are recommended where the heat load can fluctuate (such as for frequency drives) and where a continual purge is not required. The thermostat and solenoid “package” can also be added at a later date to a continuous system. An Electronic Thermostat System is also available replacing the thermostat and solenoid valve with a control box to “set” the temperature (ELC System).

If mounting cannot be on the top of the control panel an optional side mount is available (except or the 316L stainless units). Panel Coolers must be mounted vertical either at the top or at the side using the side mount.

Options

By-Pass System for Panel Coolers

Frigid-X™ By-Pass System for Panel

In very dirty environments, it can be advantageous to have a small amount of compressed air entering the control panel when the panel cooler is not operating (turned off utilizing a solenoid and thermostat package to conserve energy).  This is a “constant purge” system that will keep the control panel at a  slightly positive pressure all the time to prevent dirty environmental air from entering, thereby keeping the control panel clean.

Muffling Kit

Muffling Kits For Cabinet Panel Coolers

In many environments where the surroundings are very quiet or if personnel are working next to control panels, the Hot End and Cold End Muffing kits can reduce the noise levels an additional 8 dBA depending on air capacity used!

Electronic Control Digital Thermostat

Electronic Temperature Control

Electronic Thermostat ELC (Electronic Control Digital Thermostat) is a way for precise control of one or two Nex Flow™ Frigid-X™ cabinet panel coolers.

Mechanical Thermostat

Mechanical Thermostat And Solenoid Valve Kit

This kit comes complete with a solenoid valve, thermostat, and a resistor. The resistor is included should you encounter rapid temperature fluctuations in the control panel causing the solenoid to cycle on and off to quickly (chattering). The resistor is installed (if needed) across the leads of the thermostat and prevents chattering by dampening the thermo switch sensitivity.

Side Mount Kit for Cabinet Panel Coolers

Side Mount Kit for Cabinet Panel Coolers

If mounting cannot be on the top of the control panel an optional Side Mount Kit for Cabinet Panel Coolers is available (except for the 316L stainless units). Enclosure Cooling System must be mounted vertical either at the top or at the side using the side mount.

Calculating Head Load

Total heat load consists of the heat transfer from outside your panel and from the heat dissipated inside the control unit.

Useful terms and conversions:

1 BTU/hr = 0.293 watts
1 BTU/hr – 0.000393 horsepower
1 Watt = 3.415 BTU/hr
1 horsepower = 2544 BTU/hr
1 Watt = 0.00134 horsepower
1 Square Foot = 0.0929 square meters
1 Square Meter = 10.76 square foot

Typical fan capacity:

4″ fan: 100 CFM (2832 LPM)
6″ fan: 220 CFM (6230 LPM)
8″ fan: 340 CFM (9628 LPM)
10″ fan 550 CFM (15574 LPM)

BTU/hr. cooling effect from fan 1.08 x (temp. inside panel in °F – temp. outside panel in degrees F) x CFM.

Watts cooling effect from fan: 0.16 x (temp. inside panel in °C – temp. outside panel in degrees C) x LPM.

Calculating BTU/hr. or Watts:

  1. Determine the heat generated inside the enclosure. Approximations may be necessary. For example, if you know the power generated inside the unit, assume 10% of the energy is dissipated as heat.
  2. For heat transfer from the outside, calculate the area exposed to the atmosphere except for the top of the control panel.
  3. Choose the internal temperature you wish to have, and choose the temperature difference between it and the maximum external temperature expected.
  4. From the conversion table that follows, determine the BTU/hr. per square foot (or watts per square meter) for the temperature difference.
  5. Multiply the panel surface area times the BTU/hr. per square foot (or watts per square meter) to get the external heat transfer in BTU/hr or in watts.
  6. Sum the internal and external heat loads calculated.
  7. If you do not know the power used in the enclosure but you can measure temperatures, then measure the temperature difference between the outside at current temperature, and the present internal cabinet temperature.
  8. Note size and number of any external fans. Provide this information to Nex Flow™  to assist in sizing the appropriate cooling system.
Temperature Difference in °F BTU/hr./sq. ft. Temperature Difference in °C Watts/sq.m
5 1.5 3 5.2
10 3.3 6 11.3
15 5.1 9 17.6
20 7.1 12 24.4
25 9.1 15 31.4
30 11.3 18 39.5
35 13.8 21 47.7
40 16.2 24 55.6

Example:

The control panel coolers has two frequency drives totaling 10 horsepower and one module rated at 100 watts. The maximum outside temperature expected is 105°F or 40.5°C. The area of the control panel cooler exposed sides, except for the top is 42 square feet or 3.9 square meters. We want the internal temperature to be 95° or 35°C.

Total internal power is 10 hp x 746 watts/hp – 7460 plus 100 watts = 7560 watts.
Assume 10% forms heat = an internal heat load of 756 watts.

Or

Total internal power is 10 hp x 2544 BTU/hp = 25440 BTU/hr plus 100 watts x 3.415 BTU/hr/watt = 25782 BTU/hr.

Assume 10% forms heat = an internal heat load of 2578 BTU/hr.

External heat load: The temperature difference between the desired temperature and the outside is 10°F or 5.5°C. Using the conversions (and interpolating where necessary) we multiply the area by the conversion factor:

42 sq. ft x 3.3 – 139 BTU/hr or 3.9 sq. m x 10.3 = 40 watts

Total Heat Load: 756 + 40 – 796 watts or 2578 + 139 – 2717 BTU/hr.

You would use a Model 61040 for constant operation or a Model 63040 for one-off control. (Rated at 2900 BTU/hr or 849 watts).

+ Overview

PRODUCT OVERVIEW

The Frigid-X series Cabinet Enclosure Cooler for electronic control panels provide a low cost method of both purging and cooling electrical and electronic control panels by using a stainless steel vortex tube to create cold air from ordinary compressed air.

Our Cabinet Enclosure Coolers are compact and can be installed in minutes through a standard electrical knockout.

Nex Flow™ Offers  4 Types of UL Listed NEMA Rated Electrical Panel Coolers:

Frigid-X Cabinet Panel Coolers NEMA Type 12 (IP-52) For Electronic Control Panels for General use in industrial environments where no direct liquid spray is applied to the unit. Stainless steel construction to hold up in corrosive environments.

Frigid-X Cabinet Panel Coolers NEMA Type 3R (IP-14) For Electronic Control Panels for Outdoor Use. Stainless steel to hold up to rain, snow, humidity and general outdoor use.

Frigid-X Panel Coolers NEMA Type 4-4X (IP-66) For Electronic Control Panels – splash resistant, for use in washdown environments as well as outdoor use. Unique patented design * for secure water tight protection. Stainless steel for food service and corrosive environments. Stainless steel also provides for long life in wet environments and for outdoor use.

Frigid-X Panel Coolers NEMA Type 4-4X-316L (IP-66) For Electronic Control Panels – all external exposed surfaces are of 316L and ideal for pharmaceutical industry and extreme corrosive environments where 303/304 stainless steel is not adequate. As with the NEMA Type 4-4x units, the cooler is splash resistant, for use in wash down environments as well as outdoor use. Unique patented design* for secure water tight protection. 316L Stainless steel for pharmaceutical grade, food service and extreme corrosive environments. Stainless steel also provides for long life in wet environment.

 

* US patent number 8,616,010 / Other  countries: Patented or Patent Pending

Note: Always question non-approved units used on electrical enclosures to assure that your panels are not damaged by inferior products.

 

 

Nex Flow™ offers a High Temperature Warning Sticker free with every Frigid-X Panel Cooler  purchased for the air conditioning of electrical and electronic control panels.  High temperature inside a control panel can be damaging to internal equipment and lead to unplanned shutdown of factory operations.  The label provides for an effective  warning with a color change indicator to ORANGE and a danger warning with  a color change indicator to RED.  Color change is reversible so when the temperature problem is corrected, the label can continue to be used indefinitely.  While it is a qualitative measurement only, it provides an ideal cautionary monitoring of possible temperature problems within a control panel.

+ Features

Features

  • Low in cost
  • Compact
  • No CFC’s
  • Fast installation
  • Stabilize enclosure temperature and humidity
  • Virtually maintenance free (No Moving Parts)
  • Mounts in a standard electrical knockout
  • Stops heat damage and nuisance tripping
  • Eliminates fans and filters
  • Prevents dirt contamination by keeping enclosure at positive pressure
  • Units applicable to all environments including high temperature to 200ºF
+ Videos

VIDEOS

+ Performance

DIMENSIONS

Contact Nex Flow™ for assistance in sizing cabinet enclosure cooler – Frigid-X series. See Below for Sizing Specifications

MODEL NO. VERSION BTU/Hr. cooling*
(WATTS)
61004A NEMA Type 12 (IP-52) Continuous Operation 290
(85)
61008A NEMA Type 12 (IP-52) Continuous Operation 580
(170)
61015A NEMA Type 12 (IP-52) Continuous Operation 1100
(322)
61025A NEMA Type 12 (IP-52) Continuous Operation 1800
(527)
61030A NEMA Type 12 (IP-52) Continuous Operation 2100
(615)
61040A NEMA Type 12 (IP-52) Continuous Operation 2900
(849)
63004A NEMA Type 12 (IP52) Continuous Operation 290
(85)
63008A NEMA Type 12 (IP-52) on-off control 580
(170)
63015A NEMA Type 12 (IP-52) on-off control 1100
(322)
63025A NEMA Type 12 (IP-52) on-off control 1800
(527)
63030A NEMA Type 12 (IP-52) on-off control 2100
(615)
63040A NEMA Type 12 (IP-52) on-off control 2900
(849)
61004R NEMA Type 3R (IP14) Continuous Operation 290
(85)
61008R NEMA Type 3R (IP-14) Continuous Operation 580
(170)
61015R NEMA Type 3R (IP-14) Continuous Operation 1100
(322)
61025R NEMA Type 3R (IP-14) Continuous Operation 1800
(527)
61030R NEMA Type 3R (IP-14) Continuous Operation 2100
(615)
61040R NEMA Type 3R (IP-14) Continuous Operation 2900
(849)
63004R NEMA Type 3R (IP-14) on-off control 290
(85)
63008R NEMA Type 3R (IP-14) on-off control 580
(170))
63015R NEMA Type 3R (IP-14) on-off control 1100
(322)
63025R NEMA Type 3R (IP-14) on-off control 21800
(527)
63030R NEMA Type 3R (IP-14) on-off control 2100
(615)
63040R NEMA Type 3R (IP-14) on-off control 2900
(849)
61104X NEMA Type 4-4X (IP-66) Continuous Operation 290
(85)
61108X NEMA Type 4-4X (IP-66) Continuous Operation 580
(170)
61115X NEMA Type 4-4X (IP-66) Continuous Operation 1100
(322)
61125X NEMA Type 4-4X (IP-66) Continuous Operation 1800
(527)
61130X NEMA Type 4-4X (IP-66) Continuous Operation 2100
(615)
61140X NEMA Type 4-4X (IP-66) Continuous Operation 2900
(849)
63104X NEMA type 4-4X (IP-66) on-off conttrol 290
(85)
63108X NEMA Type 4-4X (IP-66) on-off control 580
(170))
63115X NEMA Type 4-4X (IP-66) on-off control 1100
(322)
63125X NEMA Type 4-4X (IP-66) on-off control 21800
(527)
63130X NEMA Type 4-4X (IP-66) on-off control 2100
(615)
63140X NEMA Type 4-4X (IP-66) on-off control 2900
(849)
60115X-316L 316 L Stainless Steel NEMA Type 4-4X (IP-66) on-off control (customer supplies own filter)** 1100
(322)
60125X-316L 316 L Stainless Steel NEMA Type 4-4X (IP-66) on-off control (customer supplies own filter)** 21800
(527)
60130X-316L 316 L Stainless Steel NEMA Type 4-4X (IP-66) on-off control (customer supplies own filter)** 2100
(615)
60140X-316L 316 L Stainless Steel NEMA Type 4-4X (IP-66) on-off control (customer supplies own filter)** 2900
(849)

 

** In 316 environments normally customers will have special filtration systems for such environments already.

 

*Cooling effect based on 95°F temperature inside cabinet, 100 PSIG (6.9 BAR) compressor inlet pressure, and 70ºF (21ºC) inlet temperature.

BTU/hr. figures rounded to nearest 100 BTU/hr (1 WATT).

All Continuous Operation models include the cooling unit, filter with auto drain and cold air distribution kit.

All On-Off control units include the cooling unit, filter with auto drain, cold air distribution kit, solenoid valve and thermostat.

+ Selection

SELECTION

Panel Coolers, Panel Cooler, Panel Air Conditioner, Cabinet Enclosure Cooler, Electrical Panel Air Conditioners, Cabinet Cooling Solution, Cooler Master Cabinet, Panel Air Conditioner, Adjustable Thermostat, Electrical Panel Coolers, How to Cool Electrical Enclosures, Electronic Temperature ControlCabinet enclosure coolers come with a 5 micron filter with an automatic drain (except for the 316L stainless steel units) for the compressed air supply to insure clean, dry air and an air distribution kit to circulate the cold air inside the enclosure for even cooling.

Cabinet enclosure coolers are available with or without thermostat control.

When constant cooling and a constant positive purge is required we recommend the continuous operating version without the thermostat and solenoid valve. The cooling effect can be controlled by adding a regulator in line to reduce pressure for reduced cooling when it is not required and to conserve energy.

Systems utilizing a thermostat and solenoid valve saves air by activating the air conditioner only when the internal temperature reaches a critical level. The adjustable thermostat is factory set at 95°F but can be readjusted on site.

Thermostat and solenoid valve systems are recommended where the heat load can fluctuate (such as for frequency drives) and where a continual purge is not required. The thermostat and solenoid “package” can also be added at a later date to a continuous system. An Electronic Thermostat System is also available replacing the thermostat and solenoid valve with a control box to “set” the temperature (ELC System).

If mounting cannot be on the top of the control panel an optional side mount is available (except or the 316L stainless units). Panel Coolers must be mounted vertical either at the top or at the side using the side mount.

+ Options

Options

By-Pass System for Panel Coolers

Frigid-X™ By-Pass System for Panel

In very dirty environments, it can be advantageous to have a small amount of compressed air entering the control panel when the panel cooler is not operating (turned off utilizing a solenoid and thermostat package to conserve energy).  This is a “constant purge” system that will keep the control panel at a  slightly positive pressure all the time to prevent dirty environmental air from entering, thereby keeping the control panel clean.

Muffling Kit

Muffling Kits For Cabinet Panel Coolers

In many environments where the surroundings are very quiet or if personnel are working next to control panels, the Hot End and Cold End Muffing kits can reduce the noise levels an additional 8 dBA depending on air capacity used!

Electronic Control Digital Thermostat

Electronic Temperature Control

Electronic Thermostat ELC (Electronic Control Digital Thermostat) is a way for precise control of one or two Nex Flow™ Frigid-X™ cabinet panel coolers.

Mechanical Thermostat

Mechanical Thermostat And Solenoid Valve Kit

This kit comes complete with a solenoid valve, thermostat, and a resistor. The resistor is included should you encounter rapid temperature fluctuations in the control panel causing the solenoid to cycle on and off to quickly (chattering). The resistor is installed (if needed) across the leads of the thermostat and prevents chattering by dampening the thermo switch sensitivity.

Side Mount Kit for Cabinet Panel Coolers

Side Mount Kit for Cabinet Panel Coolers

If mounting cannot be on the top of the control panel an optional Side Mount Kit for Cabinet Panel Coolers is available (except for the 316L stainless units). Enclosure Cooling System must be mounted vertical either at the top or at the side using the side mount.

+ Calculating Heat Load

Calculating Head Load

Total heat load consists of the heat transfer from outside your panel and from the heat dissipated inside the control unit.

Useful terms and conversions:

1 BTU/hr = 0.293 watts
1 BTU/hr – 0.000393 horsepower
1 Watt = 3.415 BTU/hr
1 horsepower = 2544 BTU/hr
1 Watt = 0.00134 horsepower
1 Square Foot = 0.0929 square meters
1 Square Meter = 10.76 square foot

Typical fan capacity:

4″ fan: 100 CFM (2832 LPM)
6″ fan: 220 CFM (6230 LPM)
8″ fan: 340 CFM (9628 LPM)
10″ fan 550 CFM (15574 LPM)

BTU/hr. cooling effect from fan 1.08 x (temp. inside panel in °F – temp. outside panel in degrees F) x CFM.

Watts cooling effect from fan: 0.16 x (temp. inside panel in °C – temp. outside panel in degrees C) x LPM.

Calculating BTU/hr. or Watts:

  1. Determine the heat generated inside the enclosure. Approximations may be necessary. For example, if you know the power generated inside the unit, assume 10% of the energy is dissipated as heat.
  2. For heat transfer from the outside, calculate the area exposed to the atmosphere except for the top of the control panel.
  3. Choose the internal temperature you wish to have, and choose the temperature difference between it and the maximum external temperature expected.
  4. From the conversion table that follows, determine the BTU/hr. per square foot (or watts per square meter) for the temperature difference.
  5. Multiply the panel surface area times the BTU/hr. per square foot (or watts per square meter) to get the external heat transfer in BTU/hr or in watts.
  6. Sum the internal and external heat loads calculated.
  7. If you do not know the power used in the enclosure but you can measure temperatures, then measure the temperature difference between the outside at current temperature, and the present internal cabinet temperature.
  8. Note size and number of any external fans. Provide this information to Nex Flow™  to assist in sizing the appropriate cooling system.
Temperature Difference in °F BTU/hr./sq. ft. Temperature Difference in °C Watts/sq.m
5 1.5 3 5.2
10 3.3 6 11.3
15 5.1 9 17.6
20 7.1 12 24.4
25 9.1 15 31.4
30 11.3 18 39.5
35 13.8 21 47.7
40 16.2 24 55.6

Example:

The control panel coolers has two frequency drives totaling 10 horsepower and one module rated at 100 watts. The maximum outside temperature expected is 105°F or 40.5°C. The area of the control panel cooler exposed sides, except for the top is 42 square feet or 3.9 square meters. We want the internal temperature to be 95° or 35°C.

Total internal power is 10 hp x 746 watts/hp – 7460 plus 100 watts = 7560 watts.
Assume 10% forms heat = an internal heat load of 756 watts.

Or

Total internal power is 10 hp x 2544 BTU/hp = 25440 BTU/hr plus 100 watts x 3.415 BTU/hr/watt = 25782 BTU/hr.

Assume 10% forms heat = an internal heat load of 2578 BTU/hr.

External heat load: The temperature difference between the desired temperature and the outside is 10°F or 5.5°C. Using the conversions (and interpolating where necessary) we multiply the area by the conversion factor:

42 sq. ft x 3.3 – 139 BTU/hr or 3.9 sq. m x 10.3 = 40 watts

Total Heat Load: 756 + 40 – 796 watts or 2578 + 139 – 2717 BTU/hr.

You would use a Model 61040 for constant operation or a Model 63040 for one-off control. (Rated at 2900 BTU/hr or 849 watts).