I'm scraching my head with this one...! Street lighting circuits, the supply comes in as TN-C-S Board supply, gose to a small two way circuit board which has a single pole and nuetral and two HRC fuse outputs. 1 which goes up to the lamp column, the other goes to another colume with a simla fuse protection via a swa cable. Now here is the Question ! I'm shown by the company spark the way they do there Test Sheets, Sheet One you wright the incoming supply which is TN-C-S for the first colume.
And on Sheet Two Underground Cables, you wright the incoming supply as TN-S I thought if it comes in as TN-C-S it stays as tn-c-s maybe i need to go back to collage.!!
And on Sheet Two Underground Cables, you wright the incoming supply as TN-S I thought if it comes in as TN-C-S it stays as tn-c-s maybe i need to go back to collage.!!