EXIN EXIN Certifications CDCP Questions & Answers

• Question 11:

  Can Electro Magnetic Fields (EMF) cause data centre failures?

  A. Yes, high levels of EMF can cause data centre failures.

  B. No, only power issues will cause data centre failures.

  C. No, only cooling issues will cause data centre failures.

  D. Yes, but only EMF caused by lightning strikes.

  Correct Answer: A

  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 crashes. 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 testing

• Question 12:

  Which one of the following is used in Measuring Business Value?

  A. Regeneration Cost

  B. Scalability

  C. Reliability

  D. Upfront Cost

  Correct Answer: B

  Measuring business value is the process of assessing the benefits and costs of IT investments and initiatives in relation to the strategic objectives and priorities of the organization. One of the factors that can be used to measure business value is scalability, which is the ability of a system or component to handle increasing workloads or demands without compromising performance, quality, or functionality. Scalability is important for business value because it enables the organization to adapt to changing market conditions, customer expectations, and growth opportunities. Scalability can also reduce operational costs, increase efficiency, and improve customer satisfaction. Therefore, scalability is one of the factors that can be used in measuring business value.

• Question 13:

  Which one of the following is the last stage in Stages of Combustion?

  A. Visible Smoke

  B. Intense Heat

  C. Incipient

  D. Flaming Fire

  Correct Answer: D

  The last stage in stages of combustion is flaming fire, which occurs when the fuel vapors and oxygen are mixed in the right proportion and ignited by a flame or a spark. Flaming fire is characterized by visible flames, intense heat, and rapid oxidation. Flaming fire can cause severe damage to the data center equipment, personnel, and business continuity. Therefore, it is important to prevent or suppress flaming fire as soon as possible using appropriate fire detection and suppression systems.

• Question 14:

  What factor should be considered when placing fluorescent lighting in the data centre?

  A. Fluorescent lights should not be connected to the back-up generator.

  B. Fluorescent lights should only be installed in equipment supporting areas and not in the Computer/Server room.

  C. Fluorescent lights should not be connected to the mains power supply.

  D. Fluorescent lights should not be connected to the same UPS that supports the ICT equipment.

  Correct Answer: D

  The UPS (uninterruptible power supply) is a device that provides backup power to the ICT equipment in case of a power outage or a power quality issue. The UPS should be dedicated to the ICT equipment only, and not to other loads, such as lighting, cooling, or security systems. This is because connecting fluorescent lights to the same UPS as the ICT equipment can cause several problems, such as:

  1.

  Reducing the battery runtime of the UPS, which may not be enough to support the ICT equipment until the backup generator kicks in or the utility power is restored.

  2.

  Increasing the harmonic distortion of the UPS output, which can affect the performance and reliability of the ICT equipment and the UPS itself.

  3.

  Creating electromagnetic interference (EMI) or radio frequency interference (RFI), which can disrupt the communication and data transmission of the ICT equipment.

  4.

  Triggering false alarms or tripping the circuit breakers of the UPS, which can cause downtime or data loss.

  5.

  Therefore, fluorescent lights should not be connected to the same UPS that supports the ICT equipment. Instead, they should be connected to a separate power source, such as the utility power, the backup generator, or a different UPS.

• Question 15:

  Which one of the following is an AC Power Quality Anomaly?

  A. Signal Distortion

  B. Waveform Distortion

  C. Backup Condition

  D. Attenuation

  Correct Answer: B

  Waveform distortion is a type of AC power quality anomaly that occurs when the shape of the voltage or current waveform deviates from the ideal sinusoidal shape. Waveform distortion can be caused by nonlinear loads, such as rectifiers, inverters, variable frequency drives, and electronic devices, that draw current in pulses or harmonics. Waveform distortion can result in overheating, reduced efficiency, malfunctioning, or damage of equipment.

• Question 16:

  Which Class of Fire involves combustible metals or combustible metal alloys such as magnesium, sodium and potassium?

  A. Class A

  B. Class B

  C. Class C

  D. Class D

  Correct Answer: D

  Class D fires involve combustible metals or combustible metal alloys such as magnesium, sodium and potassium. These metals can react violently with water, air, or other chemicals, and require special extinguishing agents

• Question 17:

  Which one of the following is an example of Indirect Cost?

  A. Legal fees

  B. Damaged brand perception

  C. System recovery

  D. Cost revenues

  Correct Answer: B

  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 brandperception can affect the company's ability to attract and retain customers, partners, and investors, and thus reduce its profitability and competitiveness.

• Question 18:

  Which one of the following is a device that uses circulating chilled water to remove heat?

  A. Computer Room Air Handling Unit (CRAH)

  B. Computer Room Air System Unit (CRAS)

  C. Computer Room Air Suspension Unit (CRAS)

  D. Computer Room Air Suppression Unit (CRAS)

  Correct Answer: A

  A computer room air handling unit (CRAH) is a device that uses circulating chilled water to remove heat from the data center environment. A CRAH consists of a fan, a coil, and a filter. The fan draws the warm air from the data center and passes it through the coil, where the heat is transferred to the chilled water. The chilled water is supplied by a chiller or a cooling tower, and the cooled air is returned to the data center. A CRAH is different from a computer room air conditioning unit (CRAC), which uses a refrigerant instead of chilled water to cool the air.

• Question 19:

  The UPS vendor is offering the latest model of their UPS to you. The vendor indicates that the UPS is categorized as VFD class.

  Is this UPS a fit for your mission-critical data centre?

  A. Yes

  B. No

  C. Yes, but only if you oversize the battery bank with 10%.

  D. Yes, but only if they install it with a 12-pulse rectifier.

  Correct Answer: B

  A UPS (uninterruptible power supply) that is categorized as VFD class is not a fit for your mission-critical data centre, because it does not provide adequate protection against voltage and frequency variations. VFD stands for Voltage and Frequency Dependent, which means that the output voltage and frequency of the UPS depend on the input voltage and frequency. VFD UPSs are also known as offline, standby, or line-interactive UPSs. They typically switch to battery power only when the input power fails or goes beyond a certain threshold. However, this switching may cause a brief interruption or a transient in the output power, which can affect the performance and reliability of the ICT equipment. Moreover, VFD UPSs do not filter or regulate the input power, which means that they pass on any voltage or frequency fluctuations, harmonics, or noise to the output power. These power quality issues can also damage or degrade the ICT equipment and the data.

  For your mission-critical data centre, you need a UPS that is categorized as VFI class, which stands for Voltage and Frequency Independent. VFI UPSs are also known as online, continuous, or double-conversion UPSs. They provide a constant and clean output power that is independent of the input power. VFI UPSs convert the input AC power to DC power, and then convert it back to AC power with the desired voltage and frequency. This double conversion process isolates the output power from the input power, and eliminates any power quality issues. VFI UPSs also have zero switching time, which means that they do not cause any interruption or transient in the output power when switching to battery power. VFI UPSs are designed to protect the ICT equipment and the data from any adverse effects of voltage and frequency variations, and to ensure the highest level of availability and reliability.

• Question 20:

  The termination of the ability of a product to perform its required function can be defined as.

  A. Failure

  B. Termination

  C. Hindrance

  D. Obstacle

  Correct Answer: A

  According to the EPI Data Centre Professional (CDCP? Preparation Guide, failure is defined as "the termination of the ability of a product to perform its required function" (page 9). Failure can occur due to various reasons, such as wear and tear, design flaws, human errors, environmental factors, or external events. Failure can affect the availability, reliability, and performance of a product, system, or service.