capstone Flashcards
(13 cards)
How should a word or term not defined in AS3000 be interpreted?
By its commonly understood meaning.
AS/NZS 3000 Clause: 1.4.1
List three requirements/principles which an electrical installation shall be designed to meet.
- Protect persons, livestock and property from harmful effects
- Function correctly as intended
- Connect, operate safely and be compatible with the electricity distribution system
AS/NZS 3000 Clause: 1.6.1
What is direct contact?
Making contact with a conductor or conductive part that is live in normal service, such as an active conductor or busbar.
What type of protection protects against direct contact?
Basic protection.
What are the four methods of protection against direct contact?
- Insulation - cable insulation
- Barriers - switchboard escutcheon panel
- Obstacles - locked door to switch room
- Placing out of reach - overhead power lines
What is indirect contact?
Making contact with a conductor or conductive part that has become live under fault conditions, such as the earthed frame of an appliance.
What type of protection protects against indirect contact?
Fault protection.
What are the four methods of protection against indirect contact?
- Automatic disconnect of supply - fuse, circuit breaker or RCD
- Use of class II equipment - double insulated drill, grinder etc.
- Separation of the system - isolation transformer
- Limit to lower than shock current - ELV
Can SELV or PELV systems be used to provide both basic and fault protection according to AS3000?
Yes.
AS/NZS 3000 Clause: 1.5.7
Which section of AS3000 provides guidance on ELV?
Section 7.5.
According to AS3000, what should overcurrent protection consist of?
- Overload protection
- Short-circuit protection
AS 3000 Clause: 2.5.1.1
Which section of AS3000 states the requirements for additional protection by RCD?
Section 2.6.
List a cause of overvoltage in an electrical installation.
- Lightning
- Resonance
- Insulation breakdown near HV
- Switching functions
