440 likes | 664 Views
Bubble of Protection Complete System Protection. ITW Linx A Division of Illinois Tool Works Inc. Overview. Why Use Surge Protection? Types of Surges Technologies Standards The “Bubble of Protection” Bonding and Grounding Example. Why Use Surge Protection?. Safety
E N D
Bubble of ProtectionComplete System Protection ITW Linx A Division of Illinois Tool Works Inc.
Overview • Why Use Surge Protection? • Types of Surges • Technologies • Standards • The “Bubble of Protection” • Bonding and Grounding • Example
Why Use Surge Protection? • Safety • Protect people from electric shock • Protect equipment from damage • Protect building wiring from excessive electrical current
Why Use Surge Protection? • Safety • National Electric Code • National Fire Protection Association • Telecom equipment under Article 800 • Primary Protection at Building Entrance • Secondary protection
Why Use Surge Protection? • Safety • National Electric Code • Savings • Blown Equipment • Service Calls • Downtime • Initial Investment with Net Savings
Why Use Surge Protection? • Safety • National Electric Code • Savings • Damaged Equipments Equals….Headaches • Lost Equipment • Service Repairs • System/Business Downtime • Dissatisfied Customers • Finger Pointing (Installer, Manufacturer, etc.)
Why Use Surge Protection? • Safety • National Electric Code • Savings • Damaged Equipments Equals….Headaches • Who’s Concerned? • Telephone and Power Companies • Facility, Operations, and Telecom Managers • Architects, Installers, Contractors, Technicians • Everyone!
Types of Surges • Lightning • Most catastrophic of all surges • Does not have to be a direct hit to cause damage • A lightning strike within a few miles can be induced into aerial or buried cables • 10,000,000 Volts • 145,000 Amps (145kA)
Types of Surges • Lightning • Power Line Cross • Excess current on the Communications line • High Risk of Fire • Injury to personnel • Damage to equipment
Types of Surges • Lightning • Power Line Crosses • Induction • Current flow creates a magnetic field • Two conductors run parallel and close to one another • Field of one conductor can transfer energy to the other conductor • Example: Power is first restored following a blackout Field Current
Types of Surges • Lightning • Power Line Crosses • Induction • Electrostatic Discharge • Transfer of electrical energy from one material to another • Usually found in dry climates • Produces high voltage with low current • Feel sensation at 4kv • Maximum Voltage = 30kV • Enough energy to damage integrated circuits (~35V)
Technologies • Voltage Limiting • Gas Tube • Discharge gap between two metal electrodes • Poor control of peak voltage • Clamping voltages are too high • Discharge times are too slow • Deposits build on the discharge plates with each activating surge • OK for electromagnetic switches, but not for today’s electronics
Technologies • Voltage Limiting • Gas Tube • Solid State • Provides fast, precise, and long lasting protection • Premium alternative to gas tube protectors • Fast clamping at low voltages • Performance can significantly reduce failure rates for both protector units and surge sensitive equipment • Improved reliability makes it ideal for critical service lines
Technologies • Voltage Limiting • Gas Tube • Solid State • Current Limiting • Sneak Current Protector Fuses • Prevents the current that passes by the primary protector undetected from burning down building
Technologies • Voltage Limiting • Gas Tube • Solid State • Current Limiting • Sneak Current Protector Fuses • PTC’s • Positive Temperature Coefficient (PTC) • Automatically reset once the over current is removed • Service calls/costs are dramatically reduced • Cost of replacement fuses eliminated
Standards • National Electric Code (NEC) • National Fire Protection Agency for Safety • Article 800 - Telecommunications • All conductive paths entering or leaving a building shall be protected by a listed primary protector as soon as possible, but no more than 50 feet past the building entrance
Standards • National Electric Code (NEC) • Underwriters Laboratory (UL) • Products listed • Do not start on fire or cause a fire to be started, and • Do not cause a physical safety hazard to the use
Standards • National Electric Code (NEC) • Underwriters Laboratory (UL) • UL497 - Primary • Designed to protect against Lightning and Power Crosses • 100 Amp, 10/1000 • 600V, 350A • Three Exceptions • Large metropolitan area • Less than 140ft • <5 Thunderstorm days per year
Standards • National Electric Code (NEC) • Underwriters Laboratory (UL) • UL497 – Primary • UL497A – Secondary • Installed in series between the primary protector and the equipment • Must safely limit over currents
Standards • National Electric Code (NEC) • Underwriters Laboratory (UL) • UL497 – Primary • UL497A – Secondary • UL497B – Isolated Loop (Fire Alarm or Data Circuit) • For lines that are contained within a building and not connected to the public network outside the building • These devices protect against transients usually caused by electrostatic discharge and electrical shock • NOT INTENDED FOR LIGHTNING PROTECTION
Standards • National Electric Code (NEC) • Underwriters Laboratory (UL) • UL497 - Primary • UL497A – Secondary • UL497B – Isolated Loop (Fire Alarm or Data Circuit) • UL1449 – Transient Voltage Surge Suppressor • AC Power listing at 330V • For electrical safety, NOT equipment safety
Risk Assessment • Where is the facility (Lightning potential)? • What is the Power Quality? • Outside Extensions? • What is the Ground Quality? • How Critical is the System? • What Will It Cost to Replace the System?
Secondary Secondary CO LINES CAMPUS BUILDING MAIN BUILDING Typical Install PBX Primary Protection Telco Demarcation Secondary Primary Primary
“Bubble of Protection” • Backwards Approach • Three potential conductive paths • 1) AC Power • 2) Communications Lines (Telecom) • 3) Ground System
C.O. P R I M A R Y Bubble of Protection
Bonding & Grounding • Grounding: Establish 0V Reference • Bonding: Maintaining 0V Reference • Two Point Resistance < 0.1Ω • Direct attachment to the closest point in the building’s electrical service grounding electrode system is preferred • 90% of problems are due to improper grounding • Good grounds • Structural Steel • Electrical Service Panel
Bonding & Grounding • Ground Impedance < 1Ω • Tightness of Connections (Check Annually) • Length (Short as Possible) • Number of Bends (Straight as Possible) • Bend Radius (Generous) • Size/Gauge
Bonding & Grounding • Ground Impedance (Earth Gnd) < 1.0 ohms • Single Point Ground • Racks • Cable Trays • Raised Floor • Conduits • Structural Steel • Equipment • Cold Water Pipe • AC Panel
Bonding & Grounding • Ground Impedance (Earth Gnd) < 1.0 ohms • Single Point Ground • Protect or Ground Unused Pairs
Bonding & Grounding • Ground Impedance (Earth Gnd) < 1.0 ohms • Single Point Ground • Protect or Ground Unused Pairs • Use proper gauge wire (AWG) • Receptacle ground for small systems • TMGB for large systems
Ground Size Primary Secondary • Not specified by UL or NEC • Check Manufacturer’s Specifications • Depends on size of system and current carry capacity
Example – Airport Installation The damaged phone switch
Example – Airport Installation A Good Single Point Ground But…
Example – Airport Installation In Another Room, the Ground Wire… IT’S NOT CONNECTED TO ANYTHING!
Questions? Contact ITW Linx 800-336-5493 www.itwlinx.com