A
aaelectric
Hi all,
been trying to work this out now and carnt get my head round some of the calculations.
please see where im going wrong.
voltage drop:
so 63amp mcb supplying electric boiler, run is approx 25 meters in 16mm twin & earth.
so Mv/a/m x length x amps divided by 1000= 2.8x25x63 divided by 1000=4.41%
which means its under 5% so is ok?
also trying to work out the adiabiatic equation to see if earth is big enough:
so i worked out zs first: zs=ze+r1+r2 so ohms per meter for 16mmtwin & earth is 0.00423 per meter.
so 0.00423x25meters=0.11.
next is 230v divided by 0.11=2,090
this is where ia am stuck any help would be great
also trying to work out adiabiatic on main cable. Soo.
tncs system with ze of 0.15 at main and 1.5Ka. The flat is being feed from a 5419 60amp isolator in 16mm twin and earth. Zdb at fuseboard is 0.19 and 1.2Ka. Its about 10 meter run from main fuse, how would i go about this one.
cheersguys hopes this clears things up and someone shows an easy way of calculating this.
also when filling out the eicr where is says main earth would this be the earth in the 16mm t&e or the 16mm earth going to MET at service head.
been trying to work this out now and carnt get my head round some of the calculations.
please see where im going wrong.
voltage drop:
so 63amp mcb supplying electric boiler, run is approx 25 meters in 16mm twin & earth.
so Mv/a/m x length x amps divided by 1000= 2.8x25x63 divided by 1000=4.41%
which means its under 5% so is ok?
also trying to work out the adiabiatic equation to see if earth is big enough:
so i worked out zs first: zs=ze+r1+r2 so ohms per meter for 16mmtwin & earth is 0.00423 per meter.
so 0.00423x25meters=0.11.
next is 230v divided by 0.11=2,090
this is where ia am stuck any help would be great
also trying to work out adiabiatic on main cable. Soo.
tncs system with ze of 0.15 at main and 1.5Ka. The flat is being feed from a 5419 60amp isolator in 16mm twin and earth. Zdb at fuseboard is 0.19 and 1.2Ka. Its about 10 meter run from main fuse, how would i go about this one.
cheersguys hopes this clears things up and someone shows an easy way of calculating this.
also when filling out the eicr where is says main earth would this be the earth in the 16mm t&e or the 16mm earth going to MET at service head.