CDCP Exam Dumps - Exin EPI Data Centre Questions and Answers

According to the Certified Data Centre Professional (CDCP®) Reference Materials, the height of 1 "U" (rack unit) or "RU" (rack unit) is standardized at 1.75 inches, which is equivalent to 44.45 millimeters or 4.445 centimeters. This unit of measurement is globally used to define the internal mounting space in IT and telecommunications racks. Equipment manufacturers specify their devices’ height based on how many “U” the device occupies (for example, a 2U server is 3.5 inches high). The standardization ensures interoperability and planning efficiency within the data center environment.

The "U" (rack unit) system is essential for ensuring that racks and equipment from different manufacturers will fit together properly, facilitating modularity, expansion, and maintenance. The 1.75-inch specification is defined by several industry standards including EIA-310 and is referenced directly in the EPI CDCP training and its official exam preparation guides.

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.

According to the EPI Data Centre Training Framework, EMF is a form of electromagnetic interference (EMI) that can disrupt or damage the normal operation of electronic devices, such as servers, network cables, and IT equipment1. High levels of EMF can be generated by power equipment, cell phones, microwaves, TV and radio signals, etc., and can cause data corruption, data loss, system malfunction, and crashes23. Therefore, EMF can cause data centre failures and affect the availability, performance, and security of the data centre. To prevent or mitigate EMF, data centres should follow the best practices for data centre design, layout, cabling, grounding, shielding, and testing14.

According to the Raised Floor Installation Manual, the best practice for cutting holes in the raised floor tile is to draw a cross on the tile and when making a cut-out do not touch a line and avoid the corners1. This ensures that the structural integrity and load-bearing capacity of the tile are not compromised. Cutting holes anywhere, touching the line, or cutting the corners can weaken the tile and cause it to crack or collapse1. Additionally, the manual recommends using a drill press or a reciprocating saw with a metal or bi-metal cutting blade, and deburring all sharp edges1.

The four main components of a refrigeration circuit are the evaporator, the compressor, the condenser, and the expansion valve, according to the CDCP Preparation Guide1 and various web sources234. A refrigeration circuit is a system that transfers heat from a low-temperature region to a high-temperature region, using a working fluid called refrigerant. The refrigeration circuit operates in a closed loop, where the refrigerant changes its state from liquid to vapor and back to liquid, while absorbing and releasing heat. The four main components of the refrigeration circuit perform the following functions:

•The evaporator is a heat exchanger that absorbs heat from the low-temperature region, such as the data centre room, and transfers it to the refrigerant. The refrigerant enters the evaporator as a low-pressure, low-temperature liquid, and leaves the evaporator as a low-pressure, low-temperature vapor.

•The compressor is a mechanical device that increases the pressure and temperature of the refrigerant vapor. The refrigerant enters the compressor as a low-pressure, low-temperature vapor, and leaves the compressor as a high-pressure, high-temperature vapor.

•The condenser is another heat exchanger that releases heat from the refrigerant to the high-temperature region, such as the outside air or water. The refrigerant enters the condenser as a high-pressure, high-temperature vapor, and leaves the condenser as a high-pressure, low-temperature liquid.

•The expansion valve is a device that reduces the pressure and temperature of the refrigerant liquid. The refrigerant enters the expansion valve as a high-pressure, low-temperature liquid, and leaves the expansion valve as a low-pressure, low-temperature liquid. The expansion valve also controls the flow of the refrigerant into the evaporator, depending on the cooling load.

The requirement of Concurrently Maintainability becomes relevant starting from Rated-3, according to the Uptime Institute Tier Classification System1. Concurrently Maintainability means that any component or system in the data centre can be maintained or replaced without affecting the availability of the IT equipment. This requires having redundant capacity components and multiple independent distribution paths serving the IT equipment. Rated-3 data centres are designed to achieve Concurrently Maintainability and have a minimum uptime of 99.982%. Rated-4 data centres also have Concurrently Maintainability, but they also have Fault Tolerance, which means that they can withstand any single unplanned event without affecting the availability of the IT equipment. Rated-4 data centres have a minimum uptime of 99.995%. Rated-1 and Rated-2 data centres do not have Concurrently Maintainability, as they have only one distribution path serving the IT equipment and no redundant capacity components. Rated-1 data centres have a minimum uptime of 99.671% and Rated-2 data centres have a minimum uptime of 99.741%.

Class C fires involve energized electrical equipment, such as computers, servers, switches, cables, and wiring. These fires require the use of non-conductive extinguishing agents, such as carbon dioxide, dry chemical, or clean agent, to prevent electrical shock and damage to the equipment. Water-based extinguishers, such as Class A or K, are not suitable for Class C fires, as water can conduct electricity and cause electrocution or short circuits.

Water sprinkler systems are designed to protect the structure of a building from fire by suppressing or extinguishing the flames with water. Water sprinkler systems are typically installed in the ceiling or walls of a building and are activated by heat or smoke detectors. Water sprinkler systems can reduce the risk of fire spreading and causing structural damage to the building.

Patch cables of a lower class than the structured cabling can degrade the overall link performance, so it is best practice to use the same or higher class.

Damaged brand perception is an example of an indirect cost because it is not directly related to a specific product or service, but rather to the overall reputation and image of the company. Damaged brand perception can result from various factors, such as poor quality, customer dissatisfaction, security breaches, or negative publicity. Damaged brand perception can affect the company’s ability to attract and retain customers, partners, and investors, and thus reduce its profitability and competitiveness.