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Datacenter
CRAC (Computer Room Air Conditioning)
CRAC units are specialized air conditioners that cool datacenter air and maintain humidity.
Definition
Computer Room Air Conditioning (CRAC) units are specialized HVAC systems designed for datacenter environments. CRAC units: (1) Cool hot return air from server racks, (2) Maintain humidity (40-60% RH), (3) Filter particulates, (4) Distribute cool air through raised floors or ducted ceilings. Modern alternatives: (1) In-row coolers — placed between racks for targeted cooling, (2) Rear-door heat exchangers — liquid-cooled doors on racks, (3) Direct-to-chip liquid cooling — cold plates on CPUs/GPUs. Harch Corp uses a combination of CRAC, in-row, and direct-to-chip cooling.
Related Keywords
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Related Terms
PUE (Power Usage Effectiveness)
PUE is the ratio of total facility power to IT equipment power, measuring datacenter efficiency.
Hot Aisle / Cold Aisle
Hot aisle/cold aisle is a datacenter layout that separates cool intake air from hot exhaust air.
Datacenter
A datacenter is a facility housing computer systems and networking infrastructure for computing and storage.