Answer Posted / marios

According to the 16th edition Wiring Regulations(British
standards) regulation 433-02-01 states that:
In>=Ib
In<=Iz
I2<=1.45Iz

Note:
"Iz" is the current capacity of a cable
"In" is the nominal current (current of the load)
"I2" is the current causing effective operation of the
protective device

So to calculate the size you do the following.
First you must find the In. Then you go to Appendix 4 and
you can find the size for the conductor by checking Iz to be
grater or equal to In.

e.g. Calculating Iz for a single core PVC insulated cables,
Wiring method enclosed in conduit, System of supply 240Vrms
50Hz single phase TNC-S
SOLUTION
In=20A, Iz must be > or = to In.Go to table 4D1A. When
Iz=20A Cross Sectional Area = 2.5mm^2 (Iz=In is what we
want). So the size of a conductor for 20A must be 2.5mm^2.

If you take into consideration the Temperature (T) then you
must follow the following equation: Iz>=In/(Ca*Cg*Ci) where
Ca,Cg,Ci are constants and you must find them at Appendix 4
always according to the Temperature given and also the type
of calbe been used.

how to copy from plc ge fanuc versamax series,all input and output, adress, and printout.

2434

---

How relay works, reverse relay, master relay, os relay, earth fault relay and what is its setting point

1717

---

what is basic difference betmeen normal & flame proof motor??

1957

---

Why corona leads to production of Ozone and glow of the color VOILET?

1914

---

at work we have a 3 phase motor but on testing one phase isnt getting a reading. it runs 24 hours a day all week. stops and starts well no noise or heating. the phase isnt down to earth.is it just a bad meter reading or not? phases one and three came up with a resistance reading of 0.4 but phase 2 couldnt get anything shows up as open circuit.

1608

---

can any one know is sbi interview based on merit or based on roll number

1933

---

Proviiding the Dedicated N earth and individual Body Earths ,Finally these all looped /Now my Question :- will it not harm in case of Transformer Fault current flows in Dediacted N Earthing to Looped Body Earthing.

2137

---

it is possible to measurement of tension of slipring induction motor(SRIM)carbon brushes, any maesuring instruments are available in the markets.

1944

---

How generating electric power export to grid from the generating station ?

1816

---

how do u gauge the size of the cable ?for eg. consider a 300 sqmm L.T Cable.How do u determine the size of the cable seeing it pratically?

2042

---

Differentiate between induced emf and self inductance?

1082

---

Name of the relay of low lub oil presuure in DG sets

1990

---

should %impedance be high or low in a power transformer? if so why?

1859

---

what shall be no load voltage of 132/33 kV transformer ? is it 33 kv of 34.5 kV

2126

---

Define norton equivalent circuit?

990

---