Hi, I think I have a TT supply sourced from a neighbour’s supply next door (terraced house built in 50’s). Although it looks like the neighbour has a TNS or TNCS supply, for some reason only a Line and Neutral are fed through to my supply, no Earth. Does anyone know any reason why no Earth may have been brought through when one is available next door and why I seem to have a TT supply rather than TNCS?
There’s a single 30mA RCD before my consumer unit and I get nuisance tripping as you might expect – say about once a month. This is pretty bad as it means no fridge, freezer, all clocks reset + burglar alarm gets unhappy at the end of the day when the backup battery gets flat.
I’m 98% sure it’s nuisance tripping rather than a fault, but it’s hard to identify as there’s only 1 RCD for the whole installation and it always resets first time without tripping again.
Do you have any suggestions for what I could get done to make the installation more robust?
I was thinking something along the lines of a main 300mA type S RCD to replace the 30mA one for discrimination and then a new consumer unit with 30mA RCDs on each side.
Could the main RCD be taken out altogether as long as every circuit was 30mA RCD protected in the consumer unit, or even better individual RCBOs for everything?
Thanks for your thoughts on this.
There’s a single 30mA RCD before my consumer unit and I get nuisance tripping as you might expect – say about once a month. This is pretty bad as it means no fridge, freezer, all clocks reset + burglar alarm gets unhappy at the end of the day when the backup battery gets flat.
I’m 98% sure it’s nuisance tripping rather than a fault, but it’s hard to identify as there’s only 1 RCD for the whole installation and it always resets first time without tripping again.
Do you have any suggestions for what I could get done to make the installation more robust?
I was thinking something along the lines of a main 300mA type S RCD to replace the 30mA one for discrimination and then a new consumer unit with 30mA RCDs on each side.
Could the main RCD be taken out altogether as long as every circuit was 30mA RCD protected in the consumer unit, or even better individual RCBOs for everything?
Thanks for your thoughts on this.