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High Voltage

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Plenums/Firewalls. Standard for NFPA. Adapted by ANSI. Cable. Amount ... Important cable used in ventilation spaces = Plenum. Not allow spread of toxic gases ... – PowerPoint PPT presentation

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Title: High Voltage


1
High Voltage
  • Electrical Protection Systems

2
Electrical Standards
  • Standards
  • Cable for networks
  • Grounding
  • Bonding
  • Firewalls

3
Cable Standards
  • NEC
  • Published by NFPA
  • Revised ever 3 years
  • Minimum safety requirements
  • Electrical wiring
  • Grounding
  • Most states is law

4
NEC Standard
  • How cable burns
  • Time cable takes to catch fire
  • How long it will burn
  • Cable cover is plastic
  • Create toxic smoke
  • Standard
  • Where cable can be used

5
Plenums/Firewalls
  • Standard for NFPA
  • Adapted by ANSI
  • Cable
  • Amount of smoke
  • Type of gasses
  • Important gt cable used in ventilation spaces
    Plenum
  • Not allow spread of toxic gases
  • Firewalls
  • Walls gt Fireproof material
  • Prevent spread of fires
  • Puncture firewall
  • Wires need to go through
  • Must be filled with fire stopping materials

6
Grounding/Bonding
  • TIA/EIA 607
  • Commercial Building Grounding and Bonding
    Requirements for Telecommunications
  • Multi vendor
  • Multi product
  • Other items
  • Closeness of network to High Voltage wiring
  • Lighting Ground wire
  • Grounding rods

7
Power Fundamentals
  • Network equipment and components need AC
  • HTI does not work with electrical wiring
  • Important to understand fundamentals
  • Voltage and current
  • High Voltage
  • 120/240 volts residential
  • 120 volts gt North America
  • 240 volts gt everywhere else
  • Low Voltage
  • Ex 48 volts on phone lines

8
High Voltage Terminology
  • Circuit
  • Wiring controlled by fuse or circuit breaker
  • Ampere
  • Circuit Breaker
  • Protect devices shuts power off
  • Main Breaker
  • Turns power off on whole house
  • Breaker Box
  • Houses circuit breakers
  • Neutral Bus bar
  • Metal bar gt neutral wires connected
  • Rough-in
  • Placement of outlets, switches, lights
  • Volt
  • Measure current pressure gt VIR
  • Watt
  • Measure of energy consumption gt 60 watts or 90
    watts

9
Ohms Law
  • P power measure in watts
  • Power energy consumed
  • Power VI
  • Volts Amps
  • Ohms law
  • VIR
  • IV/R
  • RV/I

10
AC/DC Current
  • AC
  • Alternating Current
  • Used in homes
  • Reverses direction
  • 60 hertz gt 60 sine waves per second
  • DC
  • Direct Current
  • Constant value
  • Does not change direction
  • Batteries

11
Electricity
  • Home via power linesgt AC
  • Transformer
  • Increase
  • Decrease
  • Appliances use different voltages
  • PC power transformer
  • 5 Volts
  • 12 Volts

12
Home Requirements
  • Size of circuit breakers
  • Size of wire (AWG) to outlet
  • 20 amp motor
  • Requires 20 amp circuit breaker
  • Safety
  • 15 amp circuit breaker
  • 14 AWG wire for outlets
  • Devices with highest amp not to exceed 15 amps
  • Assume all devices will not be used at same time
  • Too many lights on circuit
  • Lights will appear dim
  • Ex Plug in Iron
  • Homes
  • Wires and utilities
  • 20 amp circuits gt AW/V AmpsWatts/Volts

13
SAFETY
  • HTI works with low voltage
  • Voltage applied to data cables is not noticed by
    people
  • Voltage used by network devices
  • 120 to 240 volts
  • If circuit fails
  • HTI could receive shock/die
  • NOTE Do not become complacent with high-voltage
  • Difficult to control muscles
  • Difficult to get away

14
SAFETY
  • Detect unsafe voltages
  • Electricity can cause serious injury or death
  • Hazardous voltages found in work areas
  • Keep eye
  • Circuit breakers with covers removed
  • Frayed cords
  • Loose cords
  • Damaged equipment
  • Pay attention
  • Other devices in area
  • Other workers in area
  • One-Hand Rule
  • Never touch live cable with both hands
  • Completes circuit
  • Keep 1 hand in pocket

15
Cutting/Drilling
  • HTI needs to make hole to route wire
  • Safety must be observed
  • Hit live wire
  • Hit gas pipe
  • Not dangerous but costly to repair
  • Data Wire
  • Telephone wire
  • Water pipes
  • NOTE Consult building blueprints before drilling
    in walls or floors

16
Lightning
  • Source of high voltage
  • Can be fatal
  • Safety steps
  • Outside wiring needs grounding
  • Compliance with local standards
  • Do not run wires between buildings without proper
    protection
  • Avoid wires in wet areas
  • Never install during storms

17
Electricity
  • Plan for power interruption or failures
  • Blackouts
  • Complete loss of power
  • Brownouts
  • Voltage drops
  • 80 of normal voltage
  • Sags
  • Less than a second brownout
  • Noise
  • Interference gt EMI/RFI
  • Spike
  • Increase in voltage gt Higher than normal
  • Lightning strike or electricity comes on after
    blackout
  • Surge
  • Brief increase in voltage gt last some time

18
UPS
  • Uninterruptible power supply
  • Allows equipment to run for short period of time
    after power lost
  • Protects
  • Power surges
  • Spikes
  • Brownouts
  • Contains battery
  • Comes on when senses power loss
  • Software
  • Can save data and shutdown PC
  • UPS Rating
  • Rated at 1000 watts for 1 hour
  • Will operate device that uses 1000 watts for 1
    hour

19
Surge Protectors
  • Protects against surges and spikes
  • MOV
  • Metal Oxide Veristor
  • Most common surge protector
  • Directs excess voltage to ground
  • Can still damage equipment
  • Whole House Surge Protection
  • Protects against power line surges
  • Telephone lines
  • Communication lines

20
Power adapter
  • Supplied by equipment manufacturer
  • 120 volts gt Voltage rated for use in specified
    equipment
  • If not used it could damage equipment
  • DO NOT swap adapters among equipment even if
    rated for same voltage output

21
Grounding
  • Connect electrical signals to earth
  • Uses ground conductor
  • Most houses are grounded
  • How to install Ground electrode
  • NEC handbook
  • Section 250.52

22
Electrostatic Discharge
  • Static Electricity
  • Wall on carpet example
  • ESD gt Discharge on network cable
  • Electrostatic discharge
  • Damage or destroy devices or components
  • Not harmful to humans
  • Disastrous to devices
  • Protect devices always work with
  • Protective surface
  • ESD wrist band

23
Electrical Equipment
  • Location of equipment gt power outlets
  • Accommodate for future installs
  • Minimize extension cords
  • Electrical Outlets
  • Supply power to devices
  • DO NOT combine low-voltage with high-voltage
    receptacles
  • Electric Wire Termination
  • 3 Wire conductors
  • Neutral gt Large
  • Hot gt Small
  • Ground gt DOT
  • 120 volts gt 15 to 20 amps

24
Test Voltage
  • Multi meter
  • AC Voltage range selected
  • Black probe (Negative) gt Ground slot
  • Red probe (Positive) gt HOT slot
  • This will show voltage

25
Switches
  • UL
  • Underwriter laboratories
  • 2 Testing
  • AC general use snap switches
  • Toggle switch
  • AC/DC general use switches
  • Types of switches
  • Interchangeable switches
  • Door switches
  • Key switches
  • Wet location switches
  • Low-voltage switches
  • Transform high to low voltages gt 120 to 12v

26
Lighting Fixtures
  • Light bulbs
  • Rated in watts
  • 2 Categories
  • Fluorescent
  • Incandescent
  • Both can be surface mounted or suspended from
    ceiling
  • Security
  • Light all side specially dark areas
  • Outside floodlights
  • Setup in down angle
  • Proportionate to size of home

27
Electrical Wiring
  • Devices need AC power
  • Residential power installed by electrician
  • Electrical media
  • 3 Types
  • NM cable
  • MC cable
  • AC cable

28
Electrical Media
  • Nonmetallic-sheathed cable
  • 2 Wire cable
  • 1 white wire
  • 1 black wire
  • If 3 wire
  • Additional red cable
  • Wire gauges increase (AWG) size decreases
  • 2 AWG is larger than 4 AWG
  • MC cable
  • Metal clad cable
  • Conductors
  • Copper
  • Aluminum
  • Copper-clad aluminum
  • AC
  • Armored Cable or BX cable
  • 2 Conductors
  • 2 Wire 1 white and 1 black
  • 3 wire gt 1 White, 1 red and 1 black
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