매달, 우리는 1000명 이상의 사람들이 시험 준비를 잘하고 시험을 잘 통과할 수 있도록 도와줍니다.
EXIN EPI Certified Data Centre Specialist 온라인 연습
최종 업데이트 시간: 2025년10월10일
당신은 온라인 연습 문제를 통해 EXIN CDCS 시험지식에 대해 자신이 어떻게 알고 있는지 파악한 후 시험 참가 신청 여부를 결정할 수 있다.
시험을 100% 합격하고 시험 준비 시간을 35% 절약하기를 바라며 CDCS 덤프 (최신 실제 시험 문제)를 사용 선택하여 현재 최신 60개의 시험 문제와 답을 포함하십시오.
정답:
Explanation:
A potential disadvantage of using a water mist fire suppression system is that it can rapidly increase the humidity within the data center, which may pose risks to sensitive electronic equipment.
Excessive humidity can lead to condensation, which could damage electronics and lead to short circuits or corrosion over time.
Detailed Explanation
Water mist systems use fine droplets to suppress fires by cooling and displacing heat. However, the moisture generated may raise the humidity level to the point where it exceeds safe operational limits for IT equipment. Therefore, while water mist systems are effective in fire suppression, they may not be ideal in environments where high humidity could damage sensitive equipment.
EPI Data Center Specialist
Reference: EPI guidelines advise considering the impact of humidity from fire suppression systems, particularly in environments housing electronic equipment. It’s essential to weigh the benefits of fire suppression against potential risks to operational equipment when choosing suppression methods.
정답:
Explanation:
The correct formula for calculating Phase-to-Neutral Voltage in a three-phase power system is Phase-to-Neutral Voltage = Phase-to-Phase Voltage / 1.732. This formula applies to balanced three-phase systems, where 1.732 (or √3) represents the relationship between line-to-line and line-to-neutral voltages.
Detailed Explanation
In three-phase systems, Phase-to-Phase Voltage is higher than Phase-to-Neutral Voltage by a factor of √3. Dividing the phase-to-phase voltage by 1.732 gives the phase-to-neutral voltage, which is critical for understanding power distribution in three-phase electrical systems commonly found in data centers.
EPI Data Center Specialist
Reference: EPI electrical training highlights the importance of knowing these calculations for designing and maintaining balanced power systems, which are essential for stable and efficient data center operations.
정답:
Explanation:
A 2(N+1) configuration implies two independent UPS systems, each with N+1 redundancy. This configuration provides high availability by ensuring that each UPS system can independently support the load with an additional unit for redundancy. Given the 80 kW load, this setup implies that two separate N+1 systems are running, providing reliability and fault tolerance for the data center’s power needs.
Detailed Explanation
The N+1 notation denotes that each system has one additional unit beyond what is needed to carry the load, providing redundancy. With 2(N+1), there are two such setups, ensuring that if one fails, the other can still support the load without interruption, fulfilling high availability requirements.
EPI Data Center Specialist
Reference: EPI teaches that multiple redundant systems, such as 2(N+1), enhance data center reliability by ensuring that power is maintained even if a failure occurs in one system. This meets the stringent demands for uptime in critical environments.
정답:
Explanation:
Testing smoke sensors should be conducted according to the vendor specifications to ensure compliance with safety standards and accurate results. Vendors provide specific testing procedures to account for the sensor type, environment, and operational characteristics, ensuring that tests do not damage the equipment or provide false results.
Detailed Explanation
Smoke sensors can vary by type and sensitivity, so following the vendor's recommended testing procedure ensures the sensors function correctly without risking sensor damage. Injecting smoke or using a self-test might be insufficient or could lead to inaccurate assessments if they do not align with the vendor's testing protocol.
EPI Data Center Specialist
Reference: EPI recommends adhering to manufacturer specifications for testing critical safety equipment, ensuring that tests reflect real-world conditions without compromising sensor integrity or reliability.
정답:
Explanation:
In computer rooms, replacing a wet pipe system with a pre-action system is advisable. Pre-action systems provide additional protection by requiring two triggers (e.g., heat and smoke) before water is released, minimizing the risk of accidental discharge and water damage, which is crucial for safeguarding sensitive IT equipment.
Detailed Explanation
Wet pipe systems contain water in the pipes at all times, which poses a higher risk of accidental discharge. Pre-action systems, however, only fill the pipes with water upon detection of a fire, reducing the risk of water-related damage due to leaks or malfunctions. This approach is considered best practice for environments housing sensitive electronic equipment.
EPI Data Center Specialist
Reference: EPI advises using pre-action fire suppression in data centers to reduce risks associated with accidental water release, providing a safer and more controlled fire response that better protects critical infrastructure.
정답:
Explanation:
Design changes during the implementation phase are generally allowed only when there is a strong business and/or technical justification. Changes at this stage can lead to delays, increased costs, or compromise design integrity. Thus, a rigorous assessment is required to ensure any modifications are essential and provide clear benefits or address critical issues.
Detailed Explanation
Changes post-design freeze should be minimized to avoid scope creep and additional costs. However, if a technical issue arises that would affect operational goals, or a business need warrants modification, justified changes are permissible, following an impact assessment and approval process.
EPI Data Center Specialist
Reference: EPI project management guidelines recommend a controlled change management process during implementation, allowing changes only when they align with critical objectives or address unforeseen issues that affect the project's success.
정답:
Explanation:
A spirit level bar should not be used for leveling a raised floor, as measurement errors are likely to propagate from one pedestal to the next. Spirit levels can introduce cumulative errors, leading to uneven floors, particularly in large installations where precise leveling is critical.
Detailed Explanation
Using a laser level or a precision leveling device is recommended to ensure accuracy across all floor tiles. Spirit levels, while adequate for short spans, can transfer small inaccuracies from one pedestal to another, which can cause alignment issues and floor instability over time.
EPI Data Center Specialist
Reference: EPI data center guidelines discourage the use of spirit levels for raised floors. Instead, they advocate for precision tools like laser levels that ensure consistency and accuracy in large-scale installations, aligning with best practices for raised floor construction.
정답:
Explanation:
The attenuation factor for shielding material is typically calculated using the formula A = 20 log (R / M). This equation provides the attenuation in decibels (dB), where R represents the measured electromagnetic field strength, and M is the maximum acceptable level. The logarithmic scale helps quantify how much the shielding reduces EMF levels relative to the maximum allowable value.
Detailed Explanation
This formula calculates attenuation by comparing the measured value with the acceptable threshold, with the result expressed in decibels. A higher attenuation indicates more effective shielding material, essential for environments requiring robust EMF management.
EPI Data Center Specialist
Reference: EPI standards include the use of logarithmic formulas to evaluate attenuation levels, ensuring that shielding materials provide adequate reduction in EMF to protect sensitive equipment within data centers.
정답:
Explanation:
The server’s repeated overheating despite adequate intake and exhaust temperatures suggests that dust buildup inside the server may be impeding heat transfer. Dust accumulation can obstruct airflow within the server, insulate components, and disrupt the convection-based cooling systems that regulate internal temperatures, leading to overheating and potential hardware failures.
Detailed Explanation
While the intake and exhaust temperatures appear within acceptable ranges, internal dust can reduce airflow and impede cooling efficiency, causing internal components to overheat despite seemingly normal ambient conditions. Regular cleaning and maintenance are critical for preventing dust-related issues, especially in high-powered equipment like a 5kW server.
EPI Data Center Specialist
Reference: EPI emphasizes regular maintenance to prevent dust buildup in data center equipment. Dust can significantly impact cooling efficiency and lead to overheating, which underlines the importance of routine cleaning for optimal server performance.
정답:
Explanation:
In areas with frequent and extended power outages, continuous generators with at least an N+1 configuration are necessary to ensure consistent power availability. Continuous generators are designed for prolonged operation, making them suitable for scenarios where utility power is frequently unavailable, as in this case with outages exceeding 650 hours per year. An N+1 configuration ensures redundancy, which is critical for maintaining uptime in a high-availability data center.
Detailed Explanation
Continuous generators provide reliable power over long durations, unlike standby generators, which are intended only for short-term use. The N+1 configuration ensures that there is always an additional generator available in case of failure, thus maintaining power supply even if one generator goes offline.
EPI Data Center Specialist
Reference: EPI best practices recommend continuous generators with redundancy for data centers located in areas with high power instability to maintain reliability and continuous operation.
정답:
Explanation:
Raised floor tiles with air deflectors or louvers are typically heavier than standard tiles due to the additional materials and mechanisms used to direct airflow. The added weight can pose challenges for installation and adjustment, and consideration must be given to the floor’s load capacity and ease of maintenance.
Detailed Explanation
Tiles with deflectors or louvers help direct airflow, enhancing cooling efficiency by focusing cool air where needed. However, these tiles are often heavier, which can affect handling and require reinforced raised floor systems. It's essential to factor in the weight for any floor tile replacements or installations to ensure they are compatible with the raised floor's structural capacity.
EPI Data Center Specialist
Reference: EPI data center design training mentions the potential impact of heavy tiles on floor handling and load capacity. Data center operators need to plan for safe handling and load-bearing capacity when using such specialized tiles.
정답:
Explanation:
An End of Row (EoR) design minimizes the number of network switches, as multiple racks can share a single switch at the end of a row, reducing switch counts and simplifying management. This design centralizes network switching to fewer points, which reduces the complexity and number of switches required compared to a Top of Rack (ToR) design, where each rack typically has its own switch.
Detailed Explanation
In EoR designs, each row has a single network switch that handles the connections for all racks within that row. This reduces the number of individual switches needed and centralizes network management, which is ideal for minimizing equipment and simplifying infrastructure in the data center.
EPI Data Center Specialist
Reference: EPI promotes the EoR design as a way to reduce switch counts and streamline management in data centers. This configuration allows for easier scaling and maintenance while maintaining efficient network connectivity.
정답:
Explanation:
Given the customer’s requirement to limit Total Harmonic Distortion (THDi) to below 3% and the presence of a 6-pulse SCR/Thyristor-based rectifier, an active harmonic filter is the best solution. A 6-pulse rectifier typically generates higher harmonic distortion, often exceeding 3%, especially under substantial loads like 80%. An active harmonic filter dynamically monitors and compensates for harmonic distortion, effectively reducing THDi and supporting a more power-efficient operation, aligning with the customer’s energy efficiency goals.
Detailed Explanation
Passive harmonic filters can reduce harmonics but are less effective at maintaining low THDi levels under varying loads. Active filters offer real-time correction and can achieve lower THDi levels than passive filters, especially in systems with fluctuating loads or where strict harmonic limits are required. Installing an active harmonic filter will ensure compliance with the specified THDi limits and optimize power quality.
EPI Data Center Specialist
Reference: EPI guidance on power quality management recommends active harmonic filters for environments where strict THDi levels are necessary. Active filters offer better control over harmonic levels, supporting both compliance and operational efficiency.
정답:
Explanation:
From an efficiency standpoint, Unit B with a Sensible Heat Ratio (SHR) of 0.9 is preferable. A higher SHR indicates that a greater proportion of the air conditioner's capacity is dedicated to sensible cooling (temperature reduction) rather than latent cooling (moisture removal). In data centers, sensible cooling is more critical since IT equipment primarily generates heat without adding significant moisture.
Detailed Explanation
An SHR of 0.9 means that 90% of the cooling capacity is used for sensible cooling, which is more efficient for environments like data centers where humidity control is typically less of a concern. Opting for an air conditioner with a higher SHR ensures that most of the cooling energy is focused on temperature reduction, making Unit B more efficient in this scenario.
EPI Data Center Specialist
Reference: EPI data center best practices recommend choosing cooling units with higher SHR values in data centers, as they better match the cooling needs of IT equipment. High SHR units improve cooling efficiency by concentrating on sensible heat removal, which is vital for maintaining the optimal thermal environment.
정답:
Explanation:
An air intake temperature of 25 °C (77 °F) at the top of the rack is acceptable according to data center standards and guidelines, such as those from ASHRAE. This temperature falls within the recommended range for inlet temperatures, which is typically between 18°C (64°F) and 27°C (81°F).
Detailed Explanation
ASHRAE standards provide guidelines on acceptable temperature ranges for air intake in data centers to balance cooling efficiency and equipment safety. A temperature of 25°C is within the recommended operational range, allowing data centers to optimize energy efficiency while maintaining safe conditions for IT equipment.
EPI Data Center Specialist
Reference: EPI guidelines align with ASHRAE recommendations for server intake temperatures, confirming that 25°C is within acceptable limits for most mission-critical equipment. This ensures the data center maintains an efficient and reliable environment.