an existing 120mm swa is 100m long feeding a 100a 3ph db fed by a 100a mccb
a roller shutter door is being installed adjacent the db meaning the swa will not reach once it is lifted up and over the door
the cable size is large due to the length of run? and not load? so i intend to make the swa into a switch disconnector then from there a swa to reach from the new SD to the existing db, the cable length will be around 19m and so the 120 will reduce by similar amount.
what (smaller) size cable can i install and how do i calculate it?
what other info is needed
thx in advance
a roller shutter door is being installed adjacent the db meaning the swa will not reach once it is lifted up and over the door
the cable size is large due to the length of run? and not load? so i intend to make the swa into a switch disconnector then from there a swa to reach from the new SD to the existing db, the cable length will be around 19m and so the 120 will reduce by similar amount.
what (smaller) size cable can i install and how do i calculate it?
what other info is needed
thx in advance