CDCP 1st

What is the recommended way to reduce Common Mode Noise (CMN) in the computer room?

• Install an isolation transformer with a bonding between ground and neutral

• Install a true online double conversion UPS

• Install the UPS as far as possible away from the ICT equipment

• .Use PDUs with firm factor-4b Type-7

What does the ‘Form Factor’ describe for Electrical Distribution Boards (DB)?

• Form factor describes the physical dimensions of the DB

• Form factor describes the aesthetics (looks) of the DB such as color etc.

• Form factor describes the physical separation of various functional components and connections within a DB

• Form factor describes how to assemble the various parts of the DB to become one single DB

What needs to be installed in the battery room when using Lithium-ion batteries?

• A battery management system to monitor and prevent unsafe temperatures during charging/discharging.

• High capacity air conditioning equipment since Lithium-ion batteries are sensitive to high temperatures, which can reduce their lifetime

• .A proper ventilation system since Lithium-ion batteries produce highly flammable Hydrogen gas during charging

• .A proper supply of distilled water

What is the best practice for cutting holes in the raised floor tie?

• Anywhere as data center tiles are designed to allow cut-outs anywhere

• Draw a cross on the tile and when making a cut-out do not touch a line and avoid the corners.

• Draw a line in the middle of the tile and never touch the line when making the cut

• Cut the tiles at the corner so the pedestals can be used as a vertical cable manager

When having two non-synchronized power sources, the ATS/STS need to be of the type:

• Break before make

• Make before break

• .Both make before break or break before make can be used

• Both an ATS and STS can never handle two non-synchronized sources.

A UPS has an internal battery tester, do you still need to separately test the batteries at block level?

• a.No as mentioned the battery tester is already built-in the UPS

• No, the UPS will automatically generate an alarm when the battery voltage is too low to operate

• Yes, the UPS will only test the batteries at string level which only gives an indication on the overall status of the battery string. Measurements at block level will provide more detailed information  on the status and remaining lifetime of the batteries itself

• Testing batteries using the built-in battery tester or testing the batteries at block level does not increase the battery lifetime, therefore it is not recommended

Which is the most damaging type of floor load?

• Concentrated Load / Point Load (CP/PL)

• Uniformly Distributed Load (UDL)

• Rolling Load (RL)

• All loads are equally damaging to raised floor tiles

By what are magnetic fields of the type 'H' or 'B' created?

• Magnetic fields are created when an electric current flows; the greater the current, the stronger the magnetic field

• Magnetic fields are created by the magnetic flux of the earth which varies per month

• Magnetic fields are created by voltage; the greater the voltage, the stronger the magnetic fields

• Magnetic fields are created when there is a high level of common mode noise (CMN); the greater the common mode noise (CMN), the stronger the magnetic fields

IP protection grades consist of two numbers.

Which levels of protection do they describe and what is the best protection?

• First digit; protection against the ingress of solid objects. Second digit; protection against the ingress of water/fluids. The lower the number, the better the level of protection

• First digit; protection against the ingress of solid objects. Second digit; protection against the ingress of water/fluids. The higher the number, the better the level of protection

• First digit; protection against the ingress of water/fluids. Second digit; protection against the ingress of solid objects. The higher the number, the better the level of protection

• First digit; protection against the ingress of water/fluids. Second digit; protection against the ingress of solid objects. The lower the number, the better the level of protection

Proper lighting helps to

• Improve of attentiveness, avoidance of premature fatigue and help render dangerous situations recognizable

• The ability to work more easily with colored cabling routed under a raised floor

• Better security since badges can be more easily tracked and read

• .Cost savings due to the additional radiant heat provided by the lighting system.