COMPUTER COOLING SYSTEMS

COMPUTER COOLING SYSTEMS The computer itself is the most critical piece of equipment in any data system. Because the contents of any computer generate a lot of heat, the computer must have a cooling system and it must be maintained at ALL times. The computer’s cooling system must be operating properly to ensure the computer will operate properly. The cooling system may be air cooled, liquid cooled, or a combination of air and liquid cooled. R e m e m b e r , t h e r e a r e f o u r m e t h o d s o f cooling—convection, forced air, air-to-air, and air-to-liquid. Examples of computer cooling systems are as follows: Heat sinks use convection cooling to dissipate heat in computer power supplies. Small box fans with a filter mounted in the rear of PC/desktop microcomputers use forced air cooling. Heat exchangers mounted on a module, the frame, or the-cabinet and air filters for blower units use air-to-air cooling. (Figure 2-36 is an example of a heat exchanger used on a large computer. Notice it is mounted on the side of a module.) Type III, Chilled Water/Distilled Water (CW/DW) Heat Exchanger with a CW/DW Heat Exchanger Standby is the liquid cooling system used for large water-cooled computers— primarily aboard ship. Learn how your computer is cooled, and who is responsible for the maintenance. Remember, of the four methods, shore stations use a combination of the first three—convection, forced air, and air-to-air methods of cooling. shipboard systems use a combination of all four methods—convection, forced air, air-to-air, and air-to-liquid. SUMMARY—COMPUTER CONFIGURATIONS AND HARDWARE In this chapter you have studied the various diagrams and layouts used to specify computer configurations and units, the major hardware parts of a computer system, the unit connections and cables, and the need for cooling systems. The following information highlights&e important points you should have learned. FUNCTIONAL BLOCK DIAGRAMS — Functional block diagrams provide you a detailed analysis of the principles of operation or the overall equipment, types of signals and their directional flow, and the major functional areas. FUNCTIONAL LAYOUTS —Functional layouts show the major functional areas of the computer. PHYSICAL LAYOUTS —Physical layouts show where each element/part of the computer is located. They do not show signal/signal flow. COMPUTER FRAMES/CABINETS —The Figure 2-36.—Example of a heat exchanger used by a large computer is housed in a frame or cabinet. The frame or cabinet may also contain the support areas (power supply and hardware for cooling). Frames and cabinets provide some protection against hazards such as shock, EMI or RFI, moisture, and personnel mistakes. SAFETY AND SECURITY DESIGN FEATURES —Gaskets provides moisture sealing protection and protection from RFI and EMI. Filters provide electronic (RFI and EMI) and environmental (dust and dirt protection). SUBASSEMBLIES —Sub assemblies are the electronic parts of the computer. They contain components such as transistors, resistors, and capacitors, and/or pcb’s. They may be sealed or computer mounted on the side of a module. unsealed. They may or may not have test points. 2-26