Exin CDCP Certified Data Centre Professional Exam Practice Test

Answer : B

Optical fiber cables are composed of a core, a cladding, and a coating. The core is the central part of the fiber that carries the light signal. The cladding is the layer surrounding the core that reflects the light back into the core and prevents signal loss. The coating is the protective layer that covers the cladding and provides mechanical strength and environmental protection. The specifications of an optical fiber cable indicate the dimensions of the core and the cladding in microns (m), which are one millionth of a meter. For example, a 50/125 m cable has a core diameter of 50 m and a cladding diameter of 125 m. The coating diameter is usually 250 m, but it is not part of the specifications.

Answer : D

According to the EPI Data Centre Professional (CDCP) Preparation Guide, Class K fires involve cooking appliances that use combustible cooking media such as vegetable or animal oils and fats (page 28). Class K fires require special extinguishing agents that can suppress the high-temperature flames and prevent re-ignition. Class K fires are different from Class B fires, which involve flammable liquids such as gasoline, oil, or paint.

* EPI Data Centre Professional (CDCP) Preparation Guide, page 28

* Fire Classes and Extinguishing Agents | The Fire Equipment Manufacturers' Association

Answer : C

According to the EPI Data Centre Professional (CDCP) Reference Materials, the recommended number of monitoring points for temperature measurement in a data centre is 3 per rack: one at the top, one at the middle, and one at the bottom1. This is to ensure that the temperature distribution within the rack is uniform and within the acceptable range for the equipment. The temperature sensors should be placed at the front of the rack, where the air enters the equipment, and not at the back, where the hot air exits1.

Answer : A

MTBF stands for Mean Time Between Failures, and it is the arithmetic mean of time between the failing and the subsequent running of the system in a particular time period. MTBF is a measure of reliability that indicates how often a system or component fails during its operation. MTBF can be calculated by dividing the total operating time by the number of failures over a given period. For example, if a system operates for 1000 hours and experiences 5 failures, the MTBF is 1000/5 = 200 hours.

Answer : D

An ultrasonic humidifier is a type of cool mist humidifier that uses a metallic diaphragm that vibrates at high frequencies to create water droplets that are added to the air. A fan projects these droplets into the air as mist, which then evaporates and humidifies the room. This type of humidifier rapidly vibrates the water to create a fog or mist.

Answer : D

Availability is the degree to which a system, product or component is operational and accessible when required for use. It is one of the attributes of reliability, which is the ability of a system or component to perform its required functions under stated conditions for a specified period of time. Availability can be calculated as the ratio of the expected value of the uptime (the time when the system is functional) to the total time (uptime plus downtime) of a system or component. Availability can also be influenced by factors such as maintainability, fault tolerance, redundancy, diagnostics, and logistics.

Answer : A, C, E

The fire triangle is a simple model that illustrates the three elements that a fire needs to ignite and sustain: oxygen, heat, and fuel. Oxygen is the oxidizing agent that enables the combustion reaction, heat is the energy source that raises the temperature of the fuel to its ignition point, and fuel is the material that reacts with oxygen and releases heat and light. Removing any one of these elements can extinguish a fire. For example, water can reduce the heat and the oxygen, sand or soil can smother the fuel and the oxygen, and fire extinguishers can displace the oxygen or lower the temperature.