Hello

Welcome lekule blog

Hi, I`m Sostenes, Electrical Technician and PLC`S Programmer.
Everyday I`m exploring the world of Electrical to find better solution for Automation.
together in the world. #lekule86
Join us on

Power Fuse

Power fuses  are especially suited for protecting transformers, capacitor banks, and cables in outdoor distribution substations through 34.5 kV. They incorporate precision-engineered, non damageable silver or nickel-chrome fusible elements with time-current characteristics that are precise and permanently accurate, assuring not only dependable performance, but also continued reliability of system coordination plans. With power fuses, source-side devices may be set for faster operation than practical with other power fuses or circuit breakers, thereby providing better system protection without compromising coordination.

The power fuses are offered with maximum continuous current ratings of 200 A, 300 A, 400 A, and 720 A in a variety of fault-interrupting ratings. They are available in a wide variety of ampere ratings, in three different speeds: standard, slow, and coordinating. This broad selection of ampere ratings and speeds permits close fusing to achieve maximum protection.



S&C Fused Disconnect
Advantages
  • High interrupting capacity, up to 200 kA


  • Reduces let-through energy and thus provides better protection for downstream elements.
  • Low initial cost.
2500 A Fuse-GE Class L
55kV S&C Fuse

Disadvantages

  • Not effective in resistance-grounded system (fuse will not see line-to ground [L-G] faults); upstream breaker with ground-fault element will sense/trip, causing blackout in a larger area
  • Source for single phasing (one blown fuse), which poses danger to electric motors.
  • High operating expenses
Fuse Cutout
Fuse Size for Motor Branch Circuit

Manufacturers provide selection tables. Their selection is generally based on:



  • 6.0-P.U. (per unit) motor inrush current
  • 6 s starting time
  • Two starts per hour
Fuse size selected on the above basis will not be suitable for high-inertia loads (blowers, etc.) or high-efficiency motors (starting inrush & 6.00 P.U.).

 Combination starter with fused disconnect. (Courtesy Square D Company.)


Fuse Let-Through Charts

Fuse let-through charts, as shown in, are used to determine the prospective fault current that will be available at the load side of the fuse. Thus, a lower rated device, i.e., molded-case circuit breaker, can be used in the circuit.
Prospective rms current should not be used to check the downstream equipment interrupting capacity. Compare I2 × t value or ensure that the combination has been tested and certified.
 






Fuse let-through chart

Share this:

ABOUTME

Hi all. This is deepak from Bthemez. We're providing content for Bold site and we’ve been in internet, social media and affiliate for too long time and its my profession. We are web designer & developer living India! What can I say, we are the best..

Post a Comment
My photo

Hi, I`m Sostenes, Electrical Technician and PLC`S Programmer.
Everyday I`m exploring the world of Electrical to find better solution for Automation. I believe everyday can become a Electrician with the right learning materials.
My goal with BLOG is to help you learn Electrical.

Labels

LEKULE TV EDITORIALS ARTICLES DC ROBOTICS DIGITAL SEMICONDUCTORS GENERATOR AC EXPERIMENTS MANUFACTURING-ENGINEERING REFERENCE FUNDAMENTAL OF ELECTRICITY ELECTRONICS ELECTRICAL ENGINEER MEASUREMENT TRANSDUCER & SENSOR VIDEO ARDUINO RENEWABLE ENERGY AUTOMOBILE TEARDOWN SYNCHRONOUS GENERATOR DIGITAL ELECTRONICS ELECTRICAL DISTRIBUTION CABLES AUTOMOTIVE MICROCONTROLLER SOLAR PROTECTION DIODE AND CIRCUITS BASIC ELECTRICAL ELECTRONICS MOTOR SWITCHES CIRCUIT BREAKERS CIRCUITS THEORY PANEL BUILDING ELECTRONICS DEVICES MIRACLES SWITCHGEAR ANALOG MOBILE DEVICES WEARABLES CAMERA TECHNOLOGY COMMUNICATION GENERATION BATTERIES FREE CIRCUITS INDUSTRIAL AUTOMATION SPECIAL MACHINES ELECTRICAL SAFETY ENERGY EFFIDIENCY-BUILDING DRONE CONTROL SYSTEM NUCLEAR ENERGY SMATRPHONE FILTER`S POWER BIOGAS BELT CONVEYOR MATERIAL HANDLING RELAY ELECTRICAL INSTRUMENTS ENERGY SOURCE PLC`S TRANSFORMER AC CIRCUITS CIRCUIT SCHEMATIC SYMBOLS DDISCRETE SEMICONDUCTOR CIRCUITS WIND POWER C.B DEVICES DC CIRCUITS DIODES AND RECTIFIERS FUSE SPECIAL TRANSFORMER THERMAL POWER PLANT CELL CHEMISTRY EARTHING SYSTEM ELECTRIC LAMP FUNDAMENTAL OF ELECTRICITY 2 BIPOLAR JUNCTION TRANSISTOR 555 TIMER CIRCUITS AUTOCAD BLUETOOTH C PROGRAMMING HOME AUTOMATION HYDRO POWER LOGIC GATES OPERATIONAL AMPLIFIER`S SOLID-STATE DEVICE THEORRY COMPUTER DEFECE & MILITARY FLUORESCENT LAMP INDUSTRIAL ROBOTICS ANDROID ELECTRICAL DRIVES GROUNDING SYSTEM CALCULUS REFERENCE DC METERING CIRCUITS DC NETWORK ANALYSIS ELECTRICAL SAFETY TIPS ELECTRICIAN SCHOOL ELECTRON TUBES FUNDAMENTAL OF ELECTRICITY 1 INDUCTION MACHINES INSULATIONS USB ALGEBRA REFERENCE HMI[Human Interface Machines] INDUCTION MOTOR KARNAUGH MAPPING USEUL EQUIATIONS AND CONVERSION FACTOR ANALOG INTEGRATED CIRCUITS BASIC CONCEPTS AND TEST EQUIPMENTS DIGITAL COMMUNICATION DIGITAL-ANALOG CONVERSION ELECTRICAL SOFTWARE GAS TURBINE ILLUMINATION OHM`S LAW POWER ELECTRONICS THYRISTOR BOOLEAN ALGEBRA DIGITAL INTEGRATED CIRCUITS FUNDAMENTAL OF ELECTRICITY 3 PHYSICS OF CONDUCTORS AND INSULATORS SPECIAL MOTOR STEAM POWER PLANTS TESTING TRANSMISION LINE C-BISCUIT CAPACITORS COMBINATION LOGIC FUNCTION COMPLEX NUMBERS CONTROL MOTION ELECTRICAL LAWS INVERTER LADDER DIAGRAM MULTIVIBRATORS RC AND L/R TIME CONSTANTS SCADA SERIES AND PARALLEL CIRCUITS USING THE SPICE CIRCUIT SIMULATION PROGRAM AMPLIFIERS AND ACTIVE DEVICES APPS & SOFTWARE BASIC CONCEPTS OF ELECTRICITY CONDUCTOR AND INSULATORS TABLES CONDUITS FITTING AND SUPPORTS ELECTRICAL INSTRUMENTATION SIGNALS ELECTRICAL TOOLS INDUCTORS LiDAR MAGNETISM AND ELECTROMAGNETISM PLYPHASE AC CIRCUITS RECLOSER SAFE LIVING WITH GAS AND LPG SAFETY CLOTHING STEPPER MOTOR SYNCHRONOUS MOTOR AC METRING CIRCUITS BECOME AN ELECTRICIAN BINARY ARITHMETIC BUSHING DIGITAL STORAGE MEMROY ELECTRICIAN JOBS HEAT ENGINES HOME THEATER INPECTIONS LIGHT SABER MOSFET NUMERATION SYSTEM POWER FACTORS REACTANCE AND IMPEDANCE INDUCTIVE RECTIFIER AND CONVERTERS RESONANCE SCIENTIFIC NOTATION AND METRIC PREFIXES SULFURIC ACID TROUBLESHOOTING TROUBLESHOOTING-THEORY & PRACTICE 12C BUS APPLE BATTERIES AND POWER SYSTEMS DC MOTOR DRIVES ELECTROMECHANICAL RELAYS ENERGY EFFICIENCY-LIGHT INDUSTRIAL SAFETY EQUIPMENTS MEGGER MXED-FREQUENCY AC SIGNALS PRINCIPLE OF DIGITAL COMPUTING QUESTIONS REACTANCE AND IMPEDANCE-CAPATIVE SEQUENTIAL CIRCUITS SERRIES-PARALLEL COMBINATION CIRCUITS SHIFT REGISTERS WIRELESS BUILDING SERVICES COMPRESSOR CRANES DIVIDER CIRCUIT AND KIRCHHOFF`S LAW ELECTRICAL DISTRIBUTION EQUIPMENTS 1 ELECTRICAL DISTRIBUTION EQUIPMENTS B ELECTRICAL TOOL KIT ELECTRICIAN JOB DESCRIPTION INDUSTRIAL DRIVES LAPTOP SCIENCE THERMOCOUPLE TRIGONOMENTRY REFERENCE UART oscilloscope BIOMASS CONTACTOR ELECTRIC ILLUMINATION ELECTRICAL SAFETY TRAINING ELECTROMECHANICAL FEATURED FILTER DESIGN HARDWARE JUNCTION FIELD-EFFECT TRANSISTORS NASA NUCLEAR POWER VALVE COLOR CODES ELECTRIC TRACTION FLEXIBLE ELECTRONICS FLUKE GEARMOTORS INTRODUCTION LASSER PID PUMP SEAL ELECTRICIAN CAREER ELECTRICITY SUPPLY AND DISTRIBUTION MUSIC NEUTRAL PERIODIC TABLES OF THE ELEMENTS POLYPHASE AC CIRCUITS PROJECTS REATORS SATELLITE STAR DELTA VIBRATION WATERPROOF