In this lesson,
we'll discuss powering of our data centers.
Now, data centers
are the beating heart of our digital world,
and keeping them powered under all circumstances
is crucial for the success of our business operations.
To ensure our data centers always have power available,
we must architect our infrastructure
with multiple forms of redundant power.
Now, when it comes to power, there are five key terms
that describe the current state of the power being received
by our systems.
These conditions include things like surges, spikes, sags,
undervoltage events, and full power loss events.
First, we have a surge.
Now, a surge in electrical power
means that there is a small and unexpected increase
in the amount of voltage that's being provided.
So here in the United States,
our default power supply uses 120 volts.
Now, if that went up to 125 or 130 volts
instead of remaining at 120 volts,
we would call this a slight increase
in the amount of power being received as a surge.
Second, we have a spike.
Now, a spike is a short transient voltage
that's usually going to be caused by a short circuit,
a tripped circuit breaker, a power outage,
or a lightning strike.
With a spike, you might see a default voltage of 120 volts
rise all the way up to 150 volts or 175 volts or even more.
To protect against a surge or a spike,
your systems should utilize a surge protector
or line conditioner
which will be able to remove any power levels
that are higher than about 120 volts
that are used by default here in the United States.
Third, we have a sag.
Now, a sag in electrical power
means that there is a small and unexpected decrease
in the amount of voltage that's being provided.
A sag is very similar to a surge,
but it's actually an opposite
because instead of the voltage going up,
it's actually going down.
Usually, a sag will only occur for a short period of time,
and if the decreased voltage remains fairly close
to your default level of 120 volts,
then your computers may not even lose power
or go offline during that sag.
For example, it's common to see sags drop the voltage
from 120 volts down to 117 or 115 volts instead.
And at these levels, your computers
will remain online and operational
because there's still enough power to run them.
But it could damage your hardware components over time,
and so again,
you want to use something like a line conditioner
to bring that voltage back up to the 120 volts
that you're expecting to get by your systems.
Fourth, we have an undervoltage event.
Now, an undervoltage event,
which used to be referred to as a brownout,
occurs when the voltage is reduced to lower levels,
and it usually occurs for a longer period of time.
For example, if you're expecting
to receive 120 volts of power
but the voltage level drops down to 70 or 80 volts instead,
this would be considered an undervoltage event.
In this case, the voltage will be too low
to continue operating your systems,
so your systems will go offline and power themselves down.
Fifth, we have a power loss event.
Now, a power loss event, also called a power failure
or referred to by its legacy name of a blackout,
will occur whenever there's a total loss of power
for a given period of time.
For example, if you're sitting in your home office
and the power is completely lost for a minute or two,
that would be considered a complete power loss event.
With a complete power loss event,
it's really important that you're aware
that when the power's restored,
it can actually cause a power spike to occur,
and this can damage your systems too.
So now that you have a good understanding
of the five different power conditions
that you may experience,
including surges, spikes, sags, undervoltage events,
and full loss of power events,
let's take a look at the different types of robust systems
that can help us to keep our data centers up and running
by focusing on line conditioners,
uninterruptible power supply systems,
generators, and power distribution centers
to better understand how these components help
to ensure the high availability and reliability
of our systems located within our data centers.
Now first, we have a line conditioner.
A line conditioner is used
to overcome any minor fluctuations
in the power being received by the given system.
A line conditioner is going to be used
to continue powering your systems with clean power
even in the face of a surge, a sag,
or even a more pronounced undervoltage event.
Without a line conditioner,
these types of power conditions
could cause unexpected system behavior
or the degradation of your hardware over time.
But by using a line conditioner,
we can automatically adjust
the power signal being received
as an undervoltage or overvoltage condition
and then change it back
to the standard power level of our systems
that they're expecting to receive
in order to prevent damaging our systems
or their associated hardware.
A line conditioner is a great addition to your systems,
but they're not going to keep your systems running
if you're experiencing a significant undervoltage event
or a complete power failure event.
Second, we have an uninterruptible power supply.
Now, an uninterruptible power supply, also called a UPS,
is a device that provides emergency power to a system
when the normal input power source has failed.
A UPS also provides line conditioner functions
on your behalf, as well as providing a battery backup
to maintain a consistent power level to your systems,
even when a complete power failure
of the power source has occurred.
While a UPS is a great device to use in your architecture
to ensure your systems can remain online at all times,
it is important to remember that most UPS units
will only provide 15 to 60 minutes of power
during a complete power failure.
So these UPS units are really designed
to help prevent data loss or hardware damage
during a sudden or short-duration power loss event
and not going to be something that's going to help you
for the long-term power outages.
So this brings us to our third thing,
which is known as a generator.
A generator is a machine
that converts mechanical energy into electrical energy
for use in an external circuit
through the process of electromagnetic induction.
Now, a backup generator should be installed
as part of your emergency power system architecture
so that when there's an outage of your regular power supply
for the electric grid,
the generator will be able to take over
and provide power to your devices
for an extended period of time.
Now, some smaller generators can provide just enough power
for things like emergency lighting,
while larger commercial backup generators
can actually power your entire building
or at least large portions of your building and its systems.
Generators are going to come in three main varieties,
portable gas engine generators,
permanently installed generators,
and battery inverter generators.
Now, a portable gas engine generator
is the least expensive type to operate
because it usually uses just a small gasoline engine
to convert the mechanical motion into electrical power.
These generators tend to be smaller and more portable,
but they also can't support
providing high levels of power either,
so they can't be used to power an entire building
like a large generator would.
With a portable gas engine generator, you're going to find
that they tend to be very noisy when they're operating
because of that gas engine being used,
and this also means
they require higher levels of maintenance
because they're using a gas-based engine.
These generators are usually carried
to the location where they're going to be needed.
Then the device that requires power
is going to be connected to the generator
using an extension cord.
And finally, the generator is manually started up
and run to provide that power.
So you're probably not going to be using
a portable gas generator for a large server room,
but you may be able
to keep some specialized equipment up and running
using one of these portable systems.
These generators can be run
for either a short period of time or a long period of time
depending on how much fuel you have available.
For example, I have a portable gas engine generator
that I can use if I lose power to my home,
and our small generator
will use about five gallons of fuel per day
in order to provide me with enough electricity
to run most of my lighting and my refrigerator.
But it isn't powerful enough to run my air conditioning unit
with the smaller portable generator that I have.
So if you have a larger workload power need,
you can use a permanently installed generator instead.
These permanently installed generators
usually make up the backbone
of your data center's emergency power architecture.
These permanently installed generators
rely on either diesel fuel, propane,
or other types of natural gas to operate,
and these generators tend to be very large
and they can power an entire building
during a complete power loss event
for hours, days, or even weeks at a time
depending on how much fuel your system has
in its reserve tanks.
These permanently installed generators
are directly integrated
into your data center's electrical setup,
and they're designed to kick in automatically
during a power loss event.
Battery inverter generators
are the third type of generator we have,
and they usually rely on large lead-acid batteries,
nickel-cadmium batteries, or lithium-ion batteries.
These battery inverter generators tend to be quieter
and require less maintenance
than either the portable gas engine generator
or a permanently installed diesel, propane,
or natural gas generator.
Unfortunately, most battery inverter generators
can only provide minimum wattage
or provide power for a short duration of time
during an outage,
so they aren't really designed for prolonged use.
Instead, they're useful for bridging the gap
until a longer-term backup solution,
like the diesel generator, propane generator,
or natural gas generator, can be brought online
and take over our power supply needs.
Fourth, we have power distribution centers.
Now, a power distribution center, also known as a PDC,
acts as a centralized hub where power is received
and then distributed to all of your systems
throughout your data center.
A power distribution center
is not just a massive power strip, though,
because it consists of a sophisticated system
that uses integrated circuit protection,
monitoring, and load balancing
to ensure even distribution
without overloading any of your circuits.
A PDC can also be integrated
with large uninterruptable power supplies
and large permanently installed generators
to ensure a seamless transition to a backup power system
any time you are experiencing a power event
that creates a power loss event from your power grid.
Now, in order to ensure you have solid power
to all of your devices,
you're going to need to build your data center
with multiple layers of protections and redundancies.
Your exact setup is going to be defined by your use case
and your budgetary limitations,
but most large data centers
will use rack mounted uninterrupted power supplies
to be able to provide line conditioning
and battery backup functionality
to all the servers contained within a given server rack.
These batteries are usually going to be sufficient
to maintain the power load
for all the servers in a given rack
for about 10 to 15 minutes.
Your data center should also use power distribution units
to perform line conditioning and load balancing
to each server rack from your main utility power source,
and in the case of a power loss event,
the power distribution centers
can also receive their power from backup generators
if your grid power is lost or unavailable.
These generators usually take about 30 to 60 seconds
for them to start up, and then once they come up to speed,
they'll be ready to start carrying the power load
that you need to your power distribution centers.
So remember, when it comes to powering your data centers
and protecting them against surges, spikes, sags,
undervoltage events, and complete power loss events,
you can rely on the use of line conditioners,
uninterruptible power supplies, generators,
or power distribution centers
to be able to service all of your various power loads.
Line conditioners are devices designed
to improve the quality of your power
that's being delivered to your electrical load equipment
by ensuring a stable voltage supply is being given.
An uninterruptible power supply
is a device that provides emergency power to a load
when its normal input power source will fail.
A generator is a machine
that converts mechanical energy into electrical energy
for use in an external circuit
through the process of electromagnetic induction.
And power distribution centers are specialized facilities
that receive electrical power from a primary source
and distribute it to one or more secondary circuits.
By understanding their roles and the importance of each,
we can better ensure that our digital systems remain online
and operational at all times.