Few topics generate as much controversy and argument as that of earthing and the associated topics of surge protection, shielding and lightning of electrical and electronic systems. Poor earthing practice can be the cause of continual and intermittent difficult-to-diagnose problems in a facility. This course looks at these issues from a fresh yet practical perspective and enables you to reduce expensive down time on your plant and equipment to a minimum through correct application of these principles.
This course is designed to demystify the subject of earthing and presents the subject in a clear, straightforward manner. Installation, testing and inspection procedures for industrial and commercial power systems will be examined in detail. Essentially this course is broken down into earthing, shielding and surge protection for both power and electronics systems. Earthing and surge protection for telecommunications and IT systems are examined in detail. Finally, the impact of lightning is examined and simple techniques for minimizing its impact are described.
WHO SHOULD COMPLETE THIS COURSE
- Building service designers
- Consulting engineers
- Data systems planners and managers
- Electrical and instrumentation technicians
- Electrical contractors
- Electrical engineers
- Electrical inspectors
- Electricians
- Instrumentation and control engineers
- Maintenance engineers
- Power system protection and control engineers
- Project engineers
- Safety professionals
COURSE OUTLINE
EARTHING BASICS
- Basics of earthing
- Bonding
- Lightning and surge protection
- Static charges
- Shielding
- UPS systems and their earthing practice
EARTHING OF POWER SYSTEM NEUTRAL
- Unearthed and solidly earthed systems
- Impedance earther systems
- Resonant impedance earth systems
EQUIPMENT EARTHING
- Shock hazards to the human body
- Earthing of equipment
- Operation of protective devices
- Thermal capacity of earthing wires
- Touch potential
- Induced voltages
- Multiple earthing connections
- Surge protection earthing
LIGHTING AND ITS EFFECT ON BUILDINGS AND ELECTRICAL SYSTEMS
- The incidence and probability of lightning strike
- Methods of lightning protection
- Planning for lightning protection
- Improvements to lightning protection
- Effects of lightning strike on overhead lines
- To protect or not to protect
STATIC ELECTRICITY AND PROTECTION
- What is static?
- Generation of charge
- Common examples
- Energy of a spark
- Ignition capability of a spark
- Dangers of static build-up
- Control of static
- Assessment of risks and planning
EARTH ELECTRODE SYSTEM
- Earthing electrodes
- Soil resistance
- Measuring soil resistivity
- Resistance of single rod electrodes
- Current carrying capacity of an electrode
- Measurement electrode resistance single and multiple rods
- Concrete encased electrodes
- Corrosion of electrode systems
SURGE PROTECTION OF ELECTRONIC EQUIPMENT
- What is a surge?
- Bonding of different earthing systems
- Surges and surge protection
- Principles of surge protection
- Achieving graded surge protection
ELECTRICAL NOISE AND MITIGATION
- Definitions of electric noise
- Analysis and categories of noise
- Electrostatic coupling
- Electromagnetic coupling
- Shielded isolation transformer
- Insulated earth receptacle
- Zero signal reference grid
UPS SYSTEM AND THEIR EARTHING PRACTICES
- Power quality issues
- Abnormal voltage conditions
- Susceptibility and measures to handle voltage abnormalities
- Regulating transformers
- Standby sources
- Electro-mechanical UPS
- Solid state UPS
- Multiple redundant systems
- Selection of a UPS
- Earthing practices
