Original subtitles

since this is the number that ends up on the electricity bill for your data center,

similar as how you receive electricity bill for your home each month

Wei, the difference likely is that the one for your home is, hopefully, much lower

it is the theoretical value of voltage times the current expressed in ampere

That is why the value of apparent power is indicated as VA or kVA

The relationship between VA and Watt is indicated by the Power Factor or PF

Every electrical device has a Power Factor on the input.

For the output of the UPS this is important, and an example can be seen on this slide

This is based on the formula on the slide,

you multiply the Volt-Ampere with the Power Factor.

indicates the absolute maximum power that the equipment may consume,

This assumes a fully loaded configuration with maximum CPU usage,

to determine what the real expected power consumption is going to be.

to determine what the real expected power consumption is going to be

This can be very handy when performing capacity planning calculations

There are a few options for sizing the computer room power requirements

This slide is based on the metric system,

where we can see the imperial system.

| and look at somej letails for sizing power requirements

This practice can still be followed as a guidance for low density requirements,

In case you calculate using square feet,

you multiply the number with fifty Watt

If your room is one hundred square meters,

The best option is to look at the maximum power which can be used in the rack

In the data center, you don’t want to load the breaker for more than 80 percent,

and you need to realise that a data center Ihas an expected life span of 10-15 years

on your cost to build and your cost to operate

on your cost to build and your cost to operate

Note that in the industry it has become a trend to use the terminology

"low", "medium" and "high density power,

but there is no official definition lin terms of what these numbers represent

or do you have the luxury to build your data center from scratch?

you need to verify if there is sufficient power available.

If you build a new data center, you need to verify if the utility power company

is able to supply the power that you need

You could do a quick calculation for the purpose of obtaining an indication,

is to perform a more detailed calculation, to further fine tune your design

As mentioned, from there onwards you need to consider future growth of the data centre,

Once the numbers are known, you now know the load at the output of the UPS

you add the efficiency factor of the UPS

In addition, you need to add some buffer,

If you want to be really on the safe side,

you can add another 35%. but in reality, 10-15% should be sufficient

depending on whether you are using direct expansion (DX) or chilled water cooling

Finely, you add up the total UPS input power, plus the raw power supply

required for cooling and light, overf which a safety margin of 25% is added

Note that these numbers are indicators,

and look at your own specific situation

So, once the main power is sized, you need to start looking at your backucp power

So, once the main power is sized, you need to start looking at your backup power,

Generators need to be sized appropriately,

undersized generators will not be able to support the load, causing unavailability

since it will result in cylinder glazing which will create reliability issues

you need to know the power requirements of the load in both kW and kVA.

In addition, you need to review potential inrush power requirements

For example, when a heavy load such as a chiller plant kicks in

and when that happens, the generator must be able to support this.

As mentioned previously, UPS and other systems generate harmonics,

Thereforejreyiew theharmonics created,

 as a result of, for example, variable speed drives in cooling systems.

 If you have equipment that generates a modest level of harmonics

as it is the last resort of saving the data center against utility power outages

but the principle of these batteries is

in case of a power utility failure occurs

do not exceed fifteen to twenty minutes,

and do realise that once the utility power is no longer present,

air conditioners do no longer run either,

unless additional dedicated UPS systems for air conditioners have been installed,

So, in order to rely on your generator, you need to perform regular testing

It is recommended to perform a free running test at least once a month

this for the purposes of the generator its long term reliability

It does not give you any information on the generator to start automatically

nor does it tell if the generator is able to operate under full load conditions

then the only option available would be to connect it to a load bank.

which simulates a full load condition.

which is not truly testing the generator

and normally very little is used due to only testing being performed

Some date center operators argue that as long as the generator runs,

It is recommended to get a third party specialised company to take a fuel sample,

and have it analysed in laboratory,

In some of the colder countries you may experience gelling of the diesel,

This could hinder the proper flow and injection of fuel into the cylinders,

Another often forgotten point by designers

As the name suggests, it is a device that can assist in providing power

As the name suggests, it is a device that can assist in providing power

■ There are two main UPS| technologies deployed in the data center

and the other one is known as the dynamic UPS system, also known as the rotary UPS

The static UPS is called static, since it does not contain any moving parts

The UPS consists of electronic components, such as the rectifier and the inverter

although alternative energy stroage solutions are available in the the market

Adynamic or rotary UPS is a system which is built up out of moving parts

A dynamic or rotary UPS is a system which is built up out off moving parts.

Static UPS systems are relatively complex,

which is at the heart of the UPS system.

Batteries are a cost factor, as they need to be replaced after a number of years.

Dynamic UPS systems are only available in the higher power ratings

Dynamic UPS systems are very, heavy compared to static UPS systems

Dynamic UPS systems are very noisy and often require a room with sound proofing

and there is no need for batteries apart from a few batteries to start the engine

This makes it very confusing for the data center choose the correct UPS for its purpose

This makes it very confusing for the data center to choose the correct UPS for its purpose.

 Should the input fail or exceed the defined allowable input window for frequency and voltage,

Should the input fail or exceed the defined allowable input window for frequency and voltage,

and in some data centers, these UPS systems are placed inside the ICT equipment racks.

Once the UPS switches to static bypass, it needs immediate attention to correct the situation.

Once the UPS switches to static bypass, it needs immediate attention to correct the situation.

Once the UPS switches to static bypass, it needs Immediate attention to correct the situation.

the UPS could for example run in VI mode

compared to the conventional UPS systems,

since the technology is very reliable,

tor with the [ ^ lower] resistance will carry the [ ^ mos

Transformer is required. Which K-factor do you look f(

ntenance bypass mode. Which UPS technology are you

*m to prevent unsafe temperatures during charging/dis

Copyright EPl#. All rights reserved, no reproduction in part or in full

Copyright (Pis. All rights reserved, no reproduction in part or in full

which is at extreme high frequency levels

Focusing on electromagnetic fields, you need to look at the low frequencies,

Being multiples of fifty or sixty hertz,

depending on the country in which you are operating your data center

When you visualize this on the electromagnetic spectrum,

One part is called the electrical fields, which is indicated by the letter E.

Coming back to the electrical fields,

Therefore, the higher the voltage. also the higher the E fields present

Therefore, the higher the voltage, also the higher the E fields present

so the more current that's consumed, the higher the magnetic fields,

Specifically in the United States of America, this could be a bigger concern.

since it is using a low voltage system.

Other parts of the world operate on 380 or 415 volt phase to phase.

there is not much to be worried about when it comes to electric fields,

On the secondary side, the voltage is relatively low and that will not change,

since the voltage is always stable

Magnetic fields, however, are created by current, which could vary day by day,

depending on the load in your data center

This automatical results in having more concerns about magnetic fields,

The strength of magnetic fields is often

So, a quick recap: electric fields are known as E fields and involve voltage,

So, a quick recap: electric field are known as E fields and involve voltage.

you probably want to know where these fields are coming from

and in the data center this comes from the High Tension transformers,

the UPS systems, power generator sets, main power cables, etc.

the concern is more about the main power that goes into an EDU

you could look at anything which carries a current of more than 100 amperes

Another possible concern is the lightning strike protection system

to the ground drop in the soil may appear on the outside wall of the computer room

When lightning strikes the building,

So, especially when an existing building is selected to become your date center,

or EMI and RFI could potentially cause equipment malfunctioning

Here are a few examples of some of the manufacturer's manuals,

in which they inform customers with some of the possible effects of EMF

is occurring in the radio frequency band

This slide demonstrates some of the effects of EMF on a microprocessor chip

and it's something that you would normally not see in a data center environment

Another problem, which does frequently occur, is the Hot Electron effect.

the electrons flow from the source to the drain over the N and P layers of the chip,

Due to the effects of EMF on a chip, it is possible that the electron's flow

if power cables and cooper-based network cables are too close to each other

 which could lead to poor network performance or even collapse of a network

This will occur in both unshielded and Shielded twisted pair network cabling

was created to combat alien cross-talk between network cables.

And it certainly wasn’t developed to avoid the effects of EMF on network cabling

The human body has some magnetite,

EMF has a potential impact on magnetite,

This is exactly the reason why some frequent international travelers

which then helps them to avoid the issues that are associated with jet lag

that there are a lot of standards and guidelines addressing EMF and RFI,

that there are a lot of standards and guidelines addressing EMF and RFI,

that there are a lot of standards' and guidelines addressing EMF and RFI,

The standard indicates the acceptable levels for EMF surrounding equipment

Exceeding the level of 37.5 milligauss

may result in the system being, affected by levels no longer acceptable,

The NCRP, the National Council on Radiation Protection and Measurements

to which humans should be exposed to for a longer period of time.

Some countries may apply stricter limits,

An electromagnetic pulse or EMP is a short burst of electromagnetic energy

This pulse has the capability to bum out

generating a high electromagnetic pulse,

It is not unthinkable that if your country does end up in a state of war

to knock out all communication networks,

Another device capable of generating an extreme high electromagnetic pulse

is by means of a compression generator

.IF exoosure levels towards humans?