Specifications

173
NLUO PMC CONTRACTOR
SIGNATURE AND SEAL SIGNATURE AND SEAL SIGNATURE AND SEAL
trench shall be filled with riddles soil, well rammed and watered to a level of 75 mm (3’-0”) above surrounding ground level.
The ground level surface of the whole trench route shall be restored properly after completion of cable laying.
(b) Inside Building :
Cables shall be laid on walls / ceilings / structure, unless specified otherwise with M.S. brackets and suitable clamps or over
claw type aluminum cleats fixed on M.S. brackets, spaced not more than 450 mm apart. G.I. Bolts of suitable sizes are to be
grouted on the wall properly for fixing the brackets.
(c) Minimum bending radius permissible in 120 for MV cables and 20d for HV cables. At joints and terminations the individuals
core of multicore cables should never be bent so that the radius is less than 15 times the diameters over the insulation.
No cable jointing is allowed between two terminals points.
3. Cable Jointing :
All cable joints shall be carried out by experiences and Licensed jointers under strict supervision. Electro plated brass cable
glands, aluminum / tinned copper cable sockets and approved jointing materials must be used. The price for cable jointing and
finishing the ends of the cable shall include all materials and shall also provide for tools and plants for the work. The cable
accessories and other associated materials shall conform to Indian Standard Specification where applicable. Proper earthing of
cable glands and armoured shall be included in the job.
4. Testing of Cables :
All cables shall be tested for insulation resistance with megger - 5000 V constant pressure meter insulation tester for HT
cables and 1000 V constant pressure megger for LV cables, before installation.
After installation and end termination, cables shall be again subjected to the above test. Insulation value for HT Cables shall
not be less than 100 mega ohms and for MV Cables 1.0 mega ohm.
After laying and jointing, the HV cables shall be subjected to high voltage pressure test before commissioning the test voltage
being as specified in I.S. 1225-1967 or latest.
5. Testing of Installation :