Hey everyone sorry i havent been on here recently!
wondered if anyone could help i have my level 3 exam tomorow,
ive took the week of revise to REVISE HARD! which i have been! although i have been doing cable calcs for ages and can normally do them. Although i just done a practice paper ( in which i have to answer sheet to compare)
and i have the mcb size wrong??
whats going on heres the question
A 230v, 6 kW single phase load is supplied by single core pvc cables in high impact pvc conduit fixed to the surface of a brick wall over a distance of 20 metres. The circuit is protected by a type C circuit breaker. The temperature is 35 degrees Celsius.
Determine
a. the design current (1 mark)
b. the installation method (1 mark)
c. the circuit breaker rating (1 mark)
d. the correction factor (1 mark)
e. the minimum cable rating (1 mark)
f. the minimum cable size. (1 mark)
heres the answers... it says
a. 6000/230 =26 A
b. from table 4a1 method 3. (here i would normally look on page 259 in my regs book, but i cant find method 3 or find the table in my on site guide? whats it on about?
c.32A ( i chose a 30 A, why have they chose 32)
d. from table 4c1 0.94 ( i got this but again wheres this table)
e 32/0.94= 34 A ( got wrong cause i chose a 30A breaker)
f From table 4d1a col 4 6mm2 41A ( again i got this wrong choosing the wrong breaker? and if i chose a 30 A its a 4mm cable so whos right? also where is this table lol!
any help would be really greatfull ive done loads of practice papers! and this has only just happened!
Really appreciate any help.
wondered if anyone could help i have my level 3 exam tomorow,
ive took the week of revise to REVISE HARD! which i have been! although i have been doing cable calcs for ages and can normally do them. Although i just done a practice paper ( in which i have to answer sheet to compare)
and i have the mcb size wrong??
whats going on heres the question
A 230v, 6 kW single phase load is supplied by single core pvc cables in high impact pvc conduit fixed to the surface of a brick wall over a distance of 20 metres. The circuit is protected by a type C circuit breaker. The temperature is 35 degrees Celsius.
Determine
a. the design current (1 mark)
b. the installation method (1 mark)
c. the circuit breaker rating (1 mark)
d. the correction factor (1 mark)
e. the minimum cable rating (1 mark)
f. the minimum cable size. (1 mark)
heres the answers... it says
a. 6000/230 =26 A
b. from table 4a1 method 3. (here i would normally look on page 259 in my regs book, but i cant find method 3 or find the table in my on site guide? whats it on about?
c.32A ( i chose a 30 A, why have they chose 32)
d. from table 4c1 0.94 ( i got this but again wheres this table)
e 32/0.94= 34 A ( got wrong cause i chose a 30A breaker)
f From table 4d1a col 4 6mm2 41A ( again i got this wrong choosing the wrong breaker? and if i chose a 30 A its a 4mm cable so whos right? also where is this table lol!
any help would be really greatfull ive done loads of practice papers! and this has only just happened!
Really appreciate any help.