Page 91 - Electrician - TT (Volume 1)
P. 91

ELECTRICIAN - CITS




           General rules for wiring
           The followings are some of the BIS regulations pertaining to wiring installation.
           1  All  the  BIS  regulations  are  recommended  by  the  National  Electric  Code(NEC).All  fitting,  accessories  and
              appliances used for wiring shall conform to Indian standard (IS mark).
           2  Sub circuit
           May be dividein to two groups
              a  lighting and fan sub circuit
              b  Power sub circuit
           Light and fan sub circuit

           •  Light and fan may be wired on a common circuit
           •  Each sub circuit have not more than a total of ten point of light, fan and 5A socket outlets
           •  The load on each sub circuit shall be restricted to 800W
           Power sub circuit

           •  The load on each sub circuit should normally restricted to 3000W
           •  The point of each sub circuit not more than two (If the load is exceeding 3000W, the wiring for that sub circuit
              shall be done in consultation with the supply authority)

           3  The current rating of the main switch and distribution board should be calculated according to the total load
              current.
           4  All plug and sockets outlets shall be of 3 pin type, the appropriate pin being connected permanently to the
              earth system.
           5  3pin ,16A sockets shall be controlled by individual switch, shall be located immediately adjacent to it.
           6  In situation, where accessible to children, it is recommended to use shuttered or inter locked socket out lets.
           7  A socket of rating higher than 16A, should be connected to double pole switch of appropriate rating.

           8  Depending on size of kitchen, 1 or 2 three pin sockets shall be provided,
           A recommended schedule of socket out lets is given below
                 Location              6A Outlets                  16A Outlets
                 Bedroom               2 to 3 Nos.                 1 No.

                 Living room           2 to 3 Nos.                 2 Nos
                 Kitchen               1 No                        2 Nos.
                 Dining room           2 Nos                       1 No.
                 Garage                1 No                        1 No.
                 Refrigerator          -                           1 No.

                 Air-conditioners      -                           1 No.
                 Verandah              1 No.                       1 No.
                 Bathroom              1 No.                       1 No.


           9  All the metal covering should be earthed.
           10 Double earthling should be provided with all machines.
           11 No switch or fuse should be installed in the earth wire.
           12  A live wire must be protected by a fuse of current rating depend up on current rating of load.
           13  All switches should be connected through live wire.



                                                           78

                                    CITS : Power - Electrician & Wireman - Lesson 20-25
   86   87   88   89   90   91   92   93   94   95   96