Isolation And Switching Flashcards
Can isolators be used for functional switching?
No because the contacts on isolators will break down from arcing when under load
What is SP-N
Single pole and neutral
What is DP
Double pole isolator
What is TP
Three pole isolator
What is TP-N
Three pole and neutral isolator
What is four pole
Four pole isolator
Where should isolation be provided? (5 places)
At the origin of the installation (main switch before board).
For every circuit (mcb, rcbo, ect).
For every item of equipment (switch).
For every motor.
For every supply (board).
What is the different between switches and isolators
Isolators will break down when switch under load due to arcing but normal switches won’t
What are the 4 types of switching? (Not switching arrangements).
Mechanical switching
Emergency switching
Funcional switching
Firefighters switch
What is mechanical switching used for?
Mechanical switching is being able to isolate a supply to safely work on the circuit.
What is emergency switching used for
Emergency switching is there just in case. This should allow you to rapidly disconnect the power in case of an emergency like a cooker isolator switch
What is functional swithcing?
Functional switching is being able to switch thing on and off with a switch like a light or socket
What is a firefighters switch?
A firefighters switch is usually found at Petrol stations and is used in emergency’s to cut electricity from a fire. These need to be outdoors
