Latest EXIN CDCS Practice Test Questions, EXIN EPI Certified Data Centre Specialist Exam Dumps [Q30-Q47]

January 4, 2026 admin 0

Categories : CDCS , EXIN

Rate this post

Latest EXIN CDCS Practice Test Questions, EXIN EPI Certified Data Centre Specialist Exam Dumps

Jan-2026 Pass EXIN CDCS Exam in First Attempt Easily

EXIN CDCS Exam Syllabus Topics:

Topic	Details
Topic 1	Data Centre Life Cycle and Standards: This section of the exam measures the skills of data center professionals and covers the various stages involved in the life cycle of a data center, from planning and design to implementation and decommissioning.
Topic 2	Designing and Implementing a Data Centre: In this module, the exam assesses the knowledge of Exin data center professionals tasked with the design and implementation of data centers. Candidates will learn the key principles of creating an efficient data center layout, including considerations for scalability, redundancy, and security.
Topic 3	Data Centre Environmental Considerations and Efficiency: This section evaluates the proficiency of data center professionals in addressing environmental factors and promoting efficiency within data center operations. The target audience, including data center managers and engineers, will be tested on their ability to identify and implement measures that enhance energy efficiency, cooling management, and sustainable practices.

Q30. A data center scores Rated-3 in mechanical, Rated-4 in electrical, and Rated-2 in telecommunications. What is the overall rating?

Rated-2

Rated-4

Rated-4 since electrical is most important

Depends on architectural rating

ANSI/TIA-942 defines that the lowest rating across all four categories determines the overall facility rating. A facility cannot claim a higher overall level unless all subsystems meet or exceed that level.
In this case:
* Mechanical = Rated-3
* Electrical = Rated-4
* Telecommunications = Rated-2
Since telecommunications only meets Rated-2, the overall facility is Rated-2, regardless of higher scores elsewhere.
This ensures that weak areas (like cabling) are not ignored, because they can compromise overall availability.
References: ANSI/TIA-942-B §5.2.3 (Overall rating determination).

Q31. What precaution shall be taken for cabling leading into an equipment rack when a data center is in a seismic- prone area?

Cables should be replaced by busbar trunking.

Cables shall be tightly organized to the rack and trays to avoid movement.

Cables can be organized in any way as it is not important.

Cables should be loosely organized to allow for movement and be latched at the connectors.

In seismic-prone areas, cables should be tightly secured to racks and cable trays to minimize movement during seismic activity. Properly securing the cables prevents them from being damaged due to excessive motion, which could lead to outages or damage to connected equipment.
Detailed Explanation:
Loose cables can be vulnerable to shaking or sudden jolts during an earthquake, increasing the risk of disconnection or damage. By tightly organizing and securing cables, you ensure they remain in place, even during significant movement, thereby maintaining connection integrity and reducing the risk of physical damage.
EPI Data Center Specialist References:
EPI training includes considerations for data centers in seismic zones, advising that cables be firmly anchored to support structures to reduce movement and mitigate potential damage during seismic events.

Q32. An MCB needs to be installed in the PDU of an ICT rack. Which breaking curve should you select?

D-Curve

C-Curve

B-Curve

A-Curve

MCBs (Miniature Circuit Breakers) are characterized by their tripping curves:
* B-Curve: Trips at 3-5 × rated current; suitable for resistive loads.
* C-Curve: Trips at 5-10 × rated current; suitable for mixed loads including ICT equipment with moderate inrush current.
* D-Curve: Trips at 10-20 × rated current; used for heavy inductive loads like motors.
* A-Curve: Very sensitive, rarely used outside specialty electronics.
Since ICT equipment like servers and network devices have moderate inrush currents (from power supplies), the recommended breaker is C-Curve. It balances protection against nuisance tripping while still ensuring fault clearance.
References: IEC 60898-1 (Circuit Breakers for Overcurrent Protection), IEC 60947-2 (LV Breakers), EXIN DCS study material: Electrical Distribution.

Q33. A computer room is fitted with a hypoxic-based fire suppression system. On what principle does it work?

It removes the heat from the fire

It lowers the oxygen levels in the room

It removes the fuel from the fire

It uses water as an extinguisher

Hypoxic air systems continuously reduce the oxygen concentration in the protected area to below the level required for combustion (typically 15-16%), while still remaining safe for human occupancy (>14%). By lowering oxygen concentration, ignition and flame propagation are prevented.
This is different from halocarbon or inert-gas clean agents, which flood the room only upon detection of fire.
Hypoxic systems are preventive, creating a permanent fire-retardant environment.
They do not remove heat (A), fuel (C), or use water (D). Their key mechanism is oxygen displacement.
References: ISO 20338 (Oxygen Reduction Systems), NFPA 770 (Standard on Hybrid Fire Extinguishing Systems).

Q34. What is the main advantage of using an End-of-Row (EoR) design?

A single Top-of-Rack (ToR) switch is more expensive than an EoR switch

You need a separate rack to install all your EoR switches

There will be fewer switches to manage (corrected typing: original said “more”)

A ToR switch has only optical interfaces

EoR centralizes access/aggregation switches at the end of each row, reducing the number of access switches compared with ToR (one per rack), which simplifies management and often lowers Ops costs.
* A, D are incorrect generalizations.
References: ANSI/TIA-942-B §8 (Telecommunications infrastructure-HDA/EoR/ToR discussion); Cisco Data Center Access Layer CVD (EoR vs ToR design considerations).

Q35. Do you need to consider bullet (ballistics) protection when designing a data center?

Bullet (ballistics) protection is required by ANSI/TIA-942 for all data centers.

Bullet (ballistics) protection is only required when the data center is located in an area with a high crime rate.

Bullet (ballistics) protection is required by ANSI/TIA-942 for data centers Rated 3/4.

Bullet (ballistics) protection is only required if the facility is a potential target or the building is in the vicinity of a potential target.

Bullet (ballistics) protection is typically considered only for data centers that are potential targets or located near such targets. While ANSI/TIA-942 does not specifically require bulletproofing for all data centers, it is prudent to consider it based on location risk assessments, especially if the facility is in a high-risk area or near critical infrastructure that could attract threats.
Detailed Explanation:
Protective measures like bulletproofing depend on the threat landscape and the data center’s exposure to risks such as crime or terrorism. Assessments for physical security are typically customized based on location-specific risks rather than being universally required by data center standards.
EPI Data Center Specialist References:
EPI guidelines emphasize customizing physical security measures based on threat assessments, suggesting that bulletproofing is appropriate in specific circumstances where the facility’s risk profile justifies additional security measures.

Q36. When installing a raised floor, can we use a spirit level bar to level the floor?

Yes, spirit level bars can be used as long as their length is longer than 60 cm/2 ft (the size of a typical raised floor tile).

No, because using a spirit level bar, a measurement error will be transferred from pedestal to pedestal.

Yes, but spirit level bars can only be used in the vertical plane.

Yes, using a spirit level bar for raised floors higher than 40 cm is preferred.

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 References:
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.

Q37. The ‘maximum exposed area’ of the fire-rated glass is defined by the supplier as 3 sqm/32 sqft. The window area is 4 sqm/43 sqft.
What would be the best option?

Do not use fire-rated glass due to the size limit and replace it with normal glass.

Split the window in two equal parts using an aluminum frame.

Split the window into parts smaller than specified as the maximum exposed area and ensure fire-rated frames are used.

Split the window in two equal parts fitted together with transparent silicon glue.

When the window area exceeds the maximum exposed area specified for fire-rated glass, it is necessary to split the window into sections that comply with the fire rating requirements. This means creating smaller sections that are each within the 3 sqm/32 sqft limit and using fire-rated frames to ensure that the entire assembly meets fire safety standards. This approach maintains the fire-rated integrity of the glass, while allowing for larger window areas.
Detailed Explanation:
Fire-rated glass is designed to contain fire and prevent it from spreading. If the window exceeds the maximum exposed area defined by the supplier, the integrity of the fire-rated glass could be compromised. By dividing the window into compliant sections with fire-rated frames, you ensure that each pane performs as intended in the event of a fire. Fire-rated frames help maintain the fire resistance across the entire assembly, making this option the best for safety and compliance.
EPI Data Center Specialist References:
EPI recommends adhering strictly to fire safety standards, especially when using materials like fire-rated glass. The guidelines emphasize that modifications should always respect the manufacturer’s specifications to ensure the system remains effective in containing and preventing the spread of fire.

Q38. You are working with a customer who requires a guarantee that THDi levels coming from the UPS should not exceed more than 3% THDi. Furthermore, he wants to run a power-efficient data center. The UPS has a 6-Pulse SCR/Thyristor based rectifier. The current load on the UPS is approximately 80%. The customer indicates they are not expecting any changes on the ICT infrastructure for the next 3 years.
What should you recommend?

Nothing, the UPS will be able to take care of the right levels of THDi

Install a passive harmonic filter on the UPS

Install an active harmonic filter on the UPS

Install an isolation transformer rated at K13 or K20

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 References:
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.

Q39. You want to make cooling more effective by setting cold aisle temperature to 4 °C (39 °F). Is this acceptable?

Yes, but only if cooling systems can maintain this continuously

Yes, as long as dewpoint doesn’t go below -9 °C (16 °F)

No, 4 °C (39 °F) is below the allowable ASHRAE range

No, intake air must be exactly 20 °C (68 °F)

According to ASHRAE TC 9.9 Thermal Guidelines (2016), the recommended intake temperature range for Class A1 ICT equipment is 18-27 °C (64-81 °F). The allowable lower limit is 15 °C (59 °F). Setting supply to 4 °C (39 °F) falls far below these limits.
Operating at such low temperatures would:
* Cause condensation risk when surfaces drop below dew point.
* Create severe energy inefficiency, as chillers would run at extremely low setpoints.
* Possibly damage hardware due to thermal shock.
Options A and B are misleading-system capability or dew point alone does not override ASHRAE guidelines. Option D is incorrect since 20 °C is a common design target, not a requirement.
Thus, supplying 4 °C is not acceptable.
References: ASHRAE TC 9.9 “Thermal Guidelines for Data Processing Environments,” ANSI/TIA-942-B §6.
5.

Q40. The air intake of the mission-critical server at the top of the rack is measuring 25 °C/77 °F.
Is this acceptable?

Yes, this is allowed according to the standards and guidelines

As long as it does not exceed the average server room temperature of 38 °C/100 °F

Depends on the ANSI/TIA-942 Rating the data center needs to comply with

No, the temperature needs to be 20 °C/68 °F

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 References:
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.

Q41. You are changing the design of the fire suppression system for your computer room from a halocarbon fire suppression system into an inert-based fire suppression system. Could you use the same formula to calculate the gas content for the gas?

No, there is a significant difference in the formula for the different types of fire suppression gases.

Yes, as long as you take the difference between the net and gross volume into account.

Yes, as long as you use the same units of measure, i.e., kg/m³ or lbs/ft³.

Yes, as long as you change the ‘S’ factor of the formula to reflect the gas type used.

The formula used to calculate the gas content differs significantly between halocarbon and inert-based fire suppression systems. Halocarbon systems function by absorbing heat, while inert systems work by reducing oxygen levels. Due to these differences in fire suppression mechanisms, distinct formulas are applied, factoring in the specific properties of each gas type and the required concentration levels.
Detailed Explanation:
Halocarbon systems like FM200 require a formula that accounts for the concentration needed for cooling, while inert gases like nitrogen or argon need a formula that calculates the volume based on oxygen displacement. As the design concentration and characteristics of these gases differ, it’s essential to use the correct formula specific to the gas type.
EPI Data Center Specialist References:
EPI recommends consulting the specific design requirements and formulas provided by each gas manufacturer when switching fire suppression systems to ensure the correct amount of gas is deployed for effective fire suppression.

Q42. You have three UPS systems connected in parallel. The UPS systems have an imbalance in the load sharing of approximately 20%.
What should you recommend?

Review the cable lengths of each UPS to the common busbar

Nothing, there is no reason for any concern

Review the common mode noise levels within the computer room

Review the harmonics levels within the computer room

An imbalance in load sharing between UPS systems connected in parallel can often result from unequal cable lengths to the common busbar. If the cabling from each UPS to the busbar varies significantly in length, it can lead to differences in impedance, resulting in uneven load distribution. Ensuring that cable lengths are consistent helps to balance the load sharing across the UPS systems.
Detailed Explanation:
Parallel UPS systems rely on uniform impedance to share loads evenly. Differences in cable lengths cause variations in resistance, leading to one or more UPS units carrying a disproportionate share of the load.
Standardizing cable lengths ensures equal impedance, which promotes balanced load sharing and prevents one UPS from being overburdened, thus maintaining overall system reliability.
EPI Data Center Specialist References:
EPI guidelines recommend checking cable lengths when load imbalances occur in parallel UPS configurations. Ensuring equal lengths is a common method to resolve impedance issues that affect load distribution, which is critical for the stable operation of redundant power systems.

Q43. It is assumed that EMF shielding material must be installed as the EMF levels coming from the transformer room into the computer room are measured at 100mG. The transformer room is approximately 10 meters away from the computer room and is separated by a corridor. You can assume that no physical issues are present for installing shielding material at any area/location.
Where should you recommend the shielding material to be installed?

As close as possible to the computer room

As close as possible to the transformer room

It does not matter, either close to the transformer room or the computer room is okay as there is no impact to cost or shielding material performance

Shielding is not required to be installed as 100mG is within the acceptable levels for computer rooms

EMF shielding is most effective when installed close to the source of the EMF, which in this case is the transformer room. Shielding at the source contains the magnetic fields before they spread, minimizing exposure throughout the facility, including the computer room.
Detailed Explanation:
Placing shielding close to the EMF source minimizes the area impacted by electromagnetic interference, as it reduces the distance over which the EMF can spread. Shielding materials near the source can absorb or redirect EMF, providing the most effective reduction of EMF levels in adjacent spaces, like the data center.
EPI Data Center Specialist References:
EPI data center training advises positioning shielding close to the EMF source to contain fields more effectively and reduce interference in critical areas. This method is more efficient and cost-effective, as it limits the spread of EMF from the point of origin.

Q44. You are installing new copper cabling.
What is the advantage or disadvantage of choosing pre-terminated category 6 or 6A cabling?

Pre-terminated cabling is already factory tested and saves installation time.

There is no advantage as most new copper cabling network designs are based on category 3 or 5E for horizontal cabling.

Pre-terminated cabling has a higher fire rating.

Pre-terminated cabling makes ordering of the copper cables more complex, as you need to know in advance on which side the male or female connector needs to be located.

Choosing pre-terminated category 6 or 6A cabling provides several advantages, primarily related to time savings and reliability. Since pre-terminated cables are factory tested, they ensure consistent quality and performance, reducing the need for additional testing during installation. This makes installation faster and more efficient, which can significantly reduce labor costs and deployment times.
Detailed Explanation:
Pre-terminated cabling systems are manufactured and tested in controlled environments, which ensures they meet industry standards for performance. This factory testing process minimizes the likelihood of faults, reducing the need for troubleshooting and retesting on-site. Moreover, pre-terminated solutions can help to streamline installations because they eliminate the need for on-site terminations, which can be time-consuming and require skilled labor.
This is especially beneficial for data centers, where rapid deployment and minimizing potential points of failure are critical to maintaining uptime. However, it is important to note that pre-terminated cables require accurate planning, as lengths and connector configurations must be predetermined.
EPI Data Center Specialist References:
According to EPI Data Center Specialist guidelines, pre-terminated cabling is advantageous in data center environments due to reduced installation time and enhanced reliability from factory testing. These attributes align with best practices for efficient data center management, where maintaining performance and minimizing downtime are priorities.

Q45. When designing a data center network, your company wants to minimize the number of network cables to install. What type of physical cabling layout would be the best choice?

Top of Rack (ToR) design

End of Row (EoR) design

Star network design using coaxial cables

It does not matter as the number of switches is not influenced by the physical cabling layout

The Top-of-Rack (ToR) cabling layout places an access switch directly inside each rack. Each server in that rack only requires a short patch cable to connect to the switch, and only one or two uplinks per rack connect to aggregation switches. This greatly reduces the number of long horizontal cables across the data hall.
In contrast, an End-of-Row (EoR) design centralizes switches at the row end, requiring long horizontal cables from each server to the row cabinet. This can lead to thousands of extra copper or fiber runs in large deployments.
ANSI/TIA-942 and Cisco Design Guides emphasize that ToR is the best solution for minimizing cable bulk, improving airflow, and reducing cost in hyperscale or dense rack environments.
Thus, if the explicit design goal is to minimize cable quantity, ToR design is superior.
References: ANSI/TIA-942-B §8.2 (Cable Topologies: ToR, MoR, EoR), Cisco Data Center Access Layer Design Guide.

Q46. What indicates the overcurrent of a fuse or breaker?

The maximum inrush current an overcurrent protection device can handle within a defined period of time

The maximum electrical current which can flow in a particular electrical system under short-circuit conditions; it is determined by the voltage and impedance of the supply system

The current at which the device will trip

The current that a fuse or breaker is able to interrupt without being destroyed or causing an electrically damaging arc

“Overcurrent” for protective devices is the condition above the device’s rated/trip value that causes operation (tripping/melting).
* A = inrush tolerance, not the definition of overcurrent.
* B = prospective short-circuit current (Ik).
References: IEC 60947-2 (LV circuit breakers, defs 2.5.13 Overcurrent; 2.3.3 Rated short-circuit breaking capacity), IEC 60269 (fuses).

Q47. What is the advantage or disadvantage of using MPO (Multi-fiber Push On)/pre-terminated fiber?

There is no advantage, as it cannot be used with OM4 optical fiber cables.

There is no advantage, as it creates additional heat load in the data center.

It speeds up installation and provides an easy upgrade to transmission speeds up to 40 Gbit/s -100 Gbit
/s.

It is a very flexible system as it can be used for both copper cables and optical fiber cables.

MPO (Multi-fiber Push On) pre-terminated fiber offers the advantage of quick installation and supports high- speed upgrades up to 40 Gbit/s and 100 Gbit/s. This technology simplifies connections by allowing multiple fibers to be connected in a single plug-and-play module, reducing installation time and making future expansions or upgrades to higher speeds easier.
Detailed Explanation:
MPO connectors consolidate multiple fiber connections into a single interface, which simplifies cable management and reduces installation complexity. This setup is particularly beneficial in data centers where high-speed networks are essential, and where rapid deployment is necessary. MPO pre-terminated fiber also supports the use of OM4 fiber, making it compatible with existing high-performance cabling infrastructure.
EPI Data Center Specialist References:
EPI training highlights that pre-terminated fiber solutions, like MPO, can greatly enhance efficiency in data centers. By reducing installation time and providing scalability for higher transmission speeds, they align with best practices for maintaining flexible and future-ready network infrastructure.

Loading …