Can a SPD be installed in a domestic installation without an earth conductor connecting it to the MET, because it will discharge the surge from the live line conductor to the neutral conductor?
Hi all reading the calculations of the effect of wiring inductance how would an SPD work in a house with no N-E bond except one possibly out in the street? Seems like they wouldn't be terribly effective
Indeed - which is why you'd normally need (at least) two. One connected L-PE and the other N-PE (CT1 - usually on TN systems) or one connected L-N and the other N-PE (CT2 - usually on TT but can also be used on TN). Sometimes two SPDs are packaged up together into single 3-terminal device - just to confuse matters.
Hi all reading the calculations of the effect of wiring inductance how would an SPD work in a house with no N-E bond except one possibly out in the street? Seems like they wouldn't be terribly effective
Indeed - which is why you'd normally need (at least) two. One connected L-PE and the other N-PE (CT1 - usually on TN systems) or one connected L-N and the other N-PE (CT2 - usually on TT but can also be used on TN). Sometimes two SPDs are packaged up together into single 3-terminal device - just to confuse matters.
