/
Chapter 6: Creating Robust Electrical System Chapter 6: Creating Robust Electrical System

Chapter 6: Creating Robust Electrical System - PowerPoint Presentation

summer
summer . @summer
Follow
350 views
Uploaded On 2022-06-11

Chapter 6: Creating Robust Electrical System - PPT Presentation

What you will learn Key element for building a reliable DC electrical system Design strategies for inroom and standby electrical infrastructure Best practice for labeling and system monitoring ID: 917362

electrical power standby system power electrical system standby room cont infrastructure circuit ups monitoring lights recommended epo server servers

Share:

Link:

Embed:

Download Presentation from below link

Download Presentation The PPT/PDF document "Chapter 6: Creating Robust Electrical Sy..." is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.


Presentation Transcript

Slide1

Chapter 6:

Creating Robust Electrical System

Slide2

What you will learn:

Key element for building a reliable DC electrical system

Design strategies for in-room and standby electrical infrastructure

Best practice for labeling and system monitoring

End-to-end testing procedures

Slide3

Recommended Electrical system Features

The system should be dependable and ensure the continuous running for DC components (servers, networking devices,…etc)

Electrical system should be studied and planed carefully

System features that need to be included in the design:

Slide4

System

features to avert unnecessary downtime.Isolated PowerAvoiding Single Points of FailureMaintenance Bypass Options

Remote Infrastructure

Management

Slide5

Recommended Electrical system Features (Cont.)

Isolated Power

D

ifferent

power source for DC

equipments

than

other

electrical devices in the

building

Avoiding single point of failure

provide

standby power system

redundancy for critical devices and functions

physical separation for key systems

don’t share circuit breakers

plan for additional electrical power in the

future

Slide6

Recommended Electrical system Features (Cont.)

Maintenance Bypass Options

Design

the system so that regular maintenance can be

performed

without the taking major

components

offline

Remote Infrastructure

Management

Consider computer based building management system for mid and large size DC

benefits of such systems would include

Early warning of problems

Savings in terms of staff and running costs

Chosen system should provide high interoperability, easy to program, graphic interface and produce useful data metrics

Slide7

In-Room Power

Electrical infrastructure elements include:

Power distribution units

Circuit breaker panels

Electrical conduits

Wiring configurations

Choose how to terminate, route and label the components

Pre power cabinet locations with power receptacles

Slide8

In-Room Power (Cont.)

Determining Power Requirements:

Electrical infrastructure should support the room with its full capacity (completely full with servers

)

The more information about incoming DC equipments the more accurate calculations for electrical

needs

Provide abundant number of

circuits

Basic formula for the maximum power needed:

max

kva

=(volts * amps)/

1000

example: for a DC with 50 cabinet locations each with two power strip (120 volts & 20 amps)

Slide9

In-Room Power (Cont.)

Power Distribution:

Run flexible electrical conduits(whips) from large power distribution units(PDU) directly to each cabinets for small DC

Use segmented power for large server environment (running electrical conduits from PDUs to circuit panels at the end of each row and then a subset of connections to server cabinet locations).

This

option would be easier to manage, less expensive more resistant to physical accidents

Power Redundancy:

Require for redundant power supply for each server and network equipment and plug each one into different receptacle

Slide10

In-Room Power (Cont.)

Figure 6-3. Direct-Connect Power

Figure 6-4.

Distributed (segmented)Power

Slide11

In-Room Power (Cont.)

Wiring, components &termination options:

Be familiar with local power requirements (220/240 volts vs. 100/127 volts) and predominant power requirements for incoming equipments

Good design practice:

Use flexible whips (easier to install, less expensive, rearranged quickly)

Use heavy gauge of wire (the lower the gauge the thicker the wire)

Don’t terminate more than one receptacle on a conduit

Avoid dirty power

Slide12

In-Room Power (Cont.)

Labeling & Documentation:

Use thorough and unambiguous signage, labeling and documentations that is understandable by everyone

Label power receptacles with the circuits they possess and the location in the circuit breaker panel where they originate.

At that breaker panel, list all of the circuits it contains and which cabinet locations they are located at

Use color-code to indicate parallel infrastructure

Create a blue print of the room during construction (as-built) and keep it updated

Mark electrical equipments that users need to stay away from it with hazard tapes

Slide13

In-Room Power (Cont.)

Convenience Outlets:

Install convenience electrical outlets in multiple locations to be used instead of cabinet power outlets for rechargeable batteries, power drill, vacuum cleaner, …etc.

Don’t connect these outlets to the standby power system

Emergency Power Off (EPO)

Required by fire codes in many countries

Intended to prevent fire suppression materials from coming into contact with live electrical current

EPO types:

Push-up button (easy to use, most common EPO controls)

Pop-up button (second frequently used, require a new piece of glass to restore power, accidental activation is less likely)

Control Knob (require the knob to be rotated 90 degrees to activate, better design, simple to use, accidental activation is less likely)

It is highly recommended to cover EPO controls with a

transparent plastic shell, wired to an audio

alarm

.

Slide14

In-Room Power (Cont.)

Figure 6-6. Sample Emergency Power Off Controls

Slide15

Standby Power

Aimed to keep servers & network devices running when main powers fails

3 factors for designing standby system

Redundancy (the more level of redundancy the more complex and expensive the system would be)

Simplicity

Cost

Load requirements (start with max.

kva

load the room can produce and then adjust in 2 ways:

Size the standby infrastructure to handle 110 to 120 percent of the projected maximum power needs

Build out your standby infrastructure based upon what level of redundancy you want for your server environment

Design the standby system to handle both network & server rooms if they are close to each other, otherwise, have separate standby infrastructure if the network room is far from the servers room

Slide16

Standby Power (Cont.)

Batteries:

UPS is considered

t

he most common source of standby power

Use one UPS for each cabinet for small server environment or temporary DC as they are portable and inexpensive

large floor-standing UPS model installed in the electrical room are used for all other size of DC as they are more robust, have greater capacity

Run time

term is used to identify how long standby infrastructure can support DC electrical load

Required run time should be built on the assumption that the room is fully loaded

Slide17

Standby Power (Cont.)

Generators:

Size the generator to support at least 10 percent more than DC maximum power capacity

Skip installing generators in small server environment with reliable utility power and invest more in installing UPS that has 2 hrs of run time

It is recommended to have generators that can run for 8 hrs before refueling

Use enclosed protected area to install generators with short distance from DC

Protect against unauthorized employees

Protect against noise and vibration

A good ventilation and enough space around the unite is required

Slide18

Standby Power (Cont.)

Monitoring Lights:

Install monitoring lights high up on the both side of the wall inside (DC entrance, end of DC major aisles), outside and other strategic locations in the DC to indicate standby system activation

Use different color demes for UPS and generators (avoid amber or white as they are used for fire alarms)

Using large rotating beacon-style lights are recommended

Installing monitoring lights outside the DC with an explanation signage with emergency phone number would help non DC users to report such incident

Slide19

Standby Power (Cont.)

Figure 6-7 Monitoring Lights for the Standby Power System

Slide20

Labeling and Documenting

Make the labeling consistent with the servers room as possible (using the same terms and labeling schemes)

Maintain a wiring diagram and keep it current

No common standards for orienting electrical switches, on common and simple practice is to mark on position for all circuits and switches

Slide21

Installation and Grounding

Installing of grounding system help protecting electrical infrastructure and people from excess electrical charges (generated by faulty circuits, static dischargers, or lightening strike)

Grounding system usually involves copper wires connected to the building steel and linked to copper rod deep in the ground (moist soil)

Install a second grounding system

“Single Reference Grid”

to provide more protection to servers and network devices from interference, it should be connected to each power distribution unite and air handler

Slide22

Testing and Verification

The contractor must perform a series of tests before any servers/devices are installed in the DC to make sure that the infrastructure work as it should be

Area of testing

Load bank test (make sure that both UPS and generator can support the level of power as designed, the goal is to check the max. capacity and runtime of the UPS)

Injection test (injecting electrical current through circuit breakers to ensure that they perform correctly during a real life power spike)

Circuit & labeling verification (

at

least

for the main breakers and recommended for all circuits)

Full power test (cutting DC utility power to verify transferring of electrical load to standby infrastructure and back again)

EPO system test (activating EPO controls to ensure that all power sources and outlets shutdown properly)

Slide23

Testing and Verification (Cont.)

Table 6-1. Typical Load Bank Test

Slide24

Testing and Verification (Cont.)

Table 6-2. Typical Full Power Test and EPO Check

Slide25

Common Problems

Power receptacles or circuit breakers are mislabeled (obtain a power tester and have two people verify all receptacles in the room)

Monitoring lights for standby power are wired incorrectly (having monitoring lights configured to engage after 30-second which may result in no one will see UPS monitoring lights activation)

Circuit breakers are left off (this may confuse people, they may think serious problem exists)