1) earthing system
2) grounding system
3) earth system
4) ground system
the arrangement of connections and devices necessary to earth an equipment or system separately or jointly
GRM: n. (1,2,3,4)
REG: British English (1,3), American English (2,4)
References:
SEE grounding
SEE earthing
SPE grounding network
SPE earthing network

ENERGY TERM COURTESY OF ENERGY.EU