Provide same protection as an earthing while measuring a circuit insulated from earth.
Advantages
Can provide 3 different functions just by flipping or removing the “box”
– 3 phases isolated from earth
– 3 phases short-circuited and isolated from earth
– Phases connected to the earth through 3 different resistors for phase ID
No switch
No need of supply, ideal for long term job
Compatible with FC2310 for work requiring multiple earthing points
