CDCS-001 Certified Data Centre Specialist (CDCS) Question and Answers

Voltage fluctuation is a systematic variation of the voltage waveform or a series of random voltage changes of small dimensions that occur over a period of time. Voltage fluctuation can be caused by a variety of factors, such as changes in demand, changes in the power system, faults on the power system, or the switching of large loads. 

Direct Current (DC) is essential for the process of electrolysis. Electrolysis is the process of breaking down a compound using an electric current. The electric current causes ions to move, which results in a chemical reaction that breaks down the compound. In order for electrolysis to work, a direct current is required, as the ions must flow in one direction. Alternating Current (AC) changes direction and would not provide a consistent flow of ions.

Heating, lighting, and turning a motor can be done by either DC or AC. Heating can be done by passing an electric current through a heating element, which can be powered by either DC or AC. Lighting can be done by passing an electric current through a light bulb, which can be powered by either DC or AC. A motor can be powered by either DC or AC, but the type of motor and the application will determine which type of current is more suitable.

The return system in an air distribution system takes the hot exhaust air from the IT equipment and returns it to the Computer Room Air Conditioner (CRAC) unit. The CRAC unit cools the hot exhaust air and recirculates it back into the data center. The return system typically includes ducts, grills, and other components that allow the hot air to be efficiently and effectively returned to the CRAC unit.

Supply system is responsible for bringing in the cooled and filtered air from the CRAC unit to the data center.

Maintenance system and regulation system are not related to air distribution system in the data center.