Online Access Free CDCS Exam Questions

A customer requires THDi from the UPS not to exceed 3% and wants high efficiency. The UPS has a 6-pulse SCR/thyristor rectifier and is loaded ~80%. Many ICT changes are expected in the next 3 years. What should you recommend?

• A.Install an active harmonic filter on the UPS
• B.Install a passive harmonic filter on the UPS
• C.Nothing; the UPS will keep THDi at the right levels
• D.Install an isolation transformer rated K13 or K20

A data center requires an audit for ANSI/TIA-942 Rated-3 compliance. Will the network architecture be part of this audit?

• A.No, as concurrent maintainability only applies to electrical and mechanical
• B.Yes, amongst other aspects the network architecture should be Rated-3 compliant with ANSI/TIA-942
• C.Yes, but only if network administration does not comply with ANSI/TIA-606
• D.No, only the type of cabling used will be audited

The computer room has high levels of H2S gas contamination. What is the best option to resolve this issue?

• A.Provide more air changes per hour by adding more fresh air to the computer room.
• B.Install air-scrubbers.
• C.Clean the room and racks with a damp/wet cloth.
• D.Vacuum the whole room using a HEPA/S-Class-based filter.

The pipes of a VESDA smoke detection system are installed at the air intake of the air conditioner inside the computer room.
Is this a good practice from an early smoke detection point of view?

• A.No, it will give a longer reaction time for the smoke detection system and there might also be bypass airflow.
• B.Yes, as this reduces the amount of piping to be installed in the data center, as all air will go through the air conditioner.
• C.No, the piping should be installed at the air exhaust of the air conditioner, as there can also be a fire inside the air conditioner itself.
• D.It depends on the type of gas-based fire suppression which will be installed.

What is the sensible heat ratio (SHR)?

• A.Ratio of the latent heat to the total of sensible plus latent heat to be removed from a conditioned space
• B.Ratio of cold-air supply to hot-air return temperature of a cooling system
• C.Ratio of the sensible heat to the total of sensible plus latent heat to be removed from a conditioned space
• D.Ratio of the cold-aisle temperature to the hot-aisle temperature