Exin CDCP Exam With Confidence Using Practice Dumps

As per Certified Data Centre Professional (CDCP®) reference materials, Common Mode Noise (CMN) is a type of electrical noise that appears equally on the line and neutral wires with respect to ground, and it can negatively affect sensitive ICT equipment. Excessive CMN at the rack level can lead to data errors, communication problems, equipment malfunctions, or even hardware damage.

The CDCP® training and the official exam preparation guide specify that the preferred level of Common Mode Noise at the rack should be less than 1 Volt, and under no circumstances should it exceed 3 Volts. Keeping CMN at these levels helps ensure the stable and reliable operation of critical data center infrastructure. Higher CMN levels indicate grounding or bonding issues, or possibly interference from electrical or mechanical sources, and must be addressed promptly.

Options A and B (CMN above 5 or 10 Volts) are not acceptable and would present a serious risk to ICT equipment operation and data integrity. Option D is incorrect, as CMN absolutely does affect ICT equipment.

A design consideration that should be implemented with an Inergen-based fire suppression system is to install pressure relief valves in the room that needs protection. Inergen is a clean agent fire suppression system that uses a mixture of inert gases (nitrogen, argon, and carbon dioxide) to displace the oxygen in the room and extinguish the fire. However, when Inergen is released into the room, it creates a sudden increase in pressure, which can damage the walls, doors, windows, and ceilings of the room. To prevent this, pressure relief valves are required to vent the excess pressure to the outside and maintain a safe pressure level inside the room. Pressure relief valves should be designed and installed in accordance with the relevant standards and codes, such as NFPA 2001 and ISO 14520.

A fire extinguisher in the data centre that is classed as ABC is not suitable, because it contains dry chemical powder that can damage the ICT equipment and the data. ABC fire extinguishers are designed to fight Class A, B, and C fires, which are fueled by combustible materials, flammable liquids or gases, and electrical equipment, respectively. However, the dry chemical powder can leave a corrosive residue on the ICT equipment, which can cause short circuits, data loss, or malfunction. Moreover, the dry chemical powder can be difficult to clean, especially from the small spaces and crevices of the ICT equipment. Therefore, ABC fire extinguishers are not recommended for data centres, and should be replaced with more suitable fire extinguishers, such as clean agent fire extinguishers, which use gas or liquid that does not leave any residue or harm the ICT equipment.