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Hi guys n girls,
Building an extension and considering extending the downstairs lighting circuit which is 1.5mm t+e.
It is on a 5 amp breaker and I do not know the current length so am unsure if I can extend to the osg maximum of 105m? Also not sure of the osg maximum for bs3871 type mcb.....
If i measure the resistance at the furthest point of the line conductor and divide by the value for 1.5 (12.10 milli ohms) in table i1 of the osg is this likely to give me an accurate figure for existing length (assuming all connections are perfect).
According to my calcs the highest allowable figure should be 3.17ohms for R1+R2 and 1.27ohms for line on its own.
Am I best just running a new lighting circuit instead on a dedicated breaker? Help or advice appreciated.
Building an extension and considering extending the downstairs lighting circuit which is 1.5mm t+e.
It is on a 5 amp breaker and I do not know the current length so am unsure if I can extend to the osg maximum of 105m? Also not sure of the osg maximum for bs3871 type mcb.....
If i measure the resistance at the furthest point of the line conductor and divide by the value for 1.5 (12.10 milli ohms) in table i1 of the osg is this likely to give me an accurate figure for existing length (assuming all connections are perfect).
According to my calcs the highest allowable figure should be 3.17ohms for R1+R2 and 1.27ohms for line on its own.
Am I best just running a new lighting circuit instead on a dedicated breaker? Help or advice appreciated.