Introduction As part of contractual and design requirements, telecom equipment destined for certain networks in the North American market has to be tested to the Network Equipment Building System (NEBS) standard and comply with its requirements. NEBS is a standard from Telcordia, formerly known as Bell Communication Research (Bellcore). Technically speaking, NEBS is the … [Read more...]
Liquid Cooling is Back
Introduction IBM announced its return to water cooling on April 19, 2005 with the introduction of a water cooled heat exchanger mounted to the back cover of a 19 inch rack. This is the first of the major datacom equipment manufacturers to employ water cooling for a rack of CMOS processors, using a cooling distribution unit supplying the water and rejecting the heat load to … [Read more...]
Review of Low Profile Cold Plate Technology for High Density Servers
Introduction Water cooling of computers was introduced more than twenty years ago, but had disappeared from the mainstream by the mid 1990s. The conversion of chip technology from bipolar to CMOS (complementary metal oxide semiconductor) was the main reason. As chip powers continue to increase, water cooling appears likely to become mainstream again. In the current market, the … [Read more...]
ASHRAE Committee Formed to Establish Thermal Guidelines for Datacom Facilities
Introduction The environment of every data center is complex and unique. Air currents within the data center have hot and cold air streams colliding, cold air exhausting upward from perforated tiles, hot air streams exhausting from tops and the rear of servers and storage racks. Not only are these air circulation patterns extremely complex, they can also be transient in nature … [Read more...]
Estimating Temperatures in an Air-cooled Closed Box Electronics Enclosure
Introduction In the majority of air-cooling applications, openings or vents are provided in the enclosure or box in which the electronic components are housed. The required cooling air is drawn in from outside the box by fans or blowers. In some applications, however, there may be airborne particulates or other substances in the air that would be injurious to the electrical … [Read more...]