ERDC-MPPL is proud to be introduced Kolomite (modern/permanent earthing solution) for the 1st time in Pakistan. Now there is no need to import the material from UK etc or using of conventional method which required maintenance. Kolomite is a ground enhancement material having resistivity of less than 0.25 Ω-m and has been developed specially to make earthing system cheap and effective according to IEEE std 80-2000 section 14.5 para requirements given on page 68 of standard section 14.5 deals with soil treatment to lower resistivity and gives various options available to achieve it.
Kolomite is recommended for both, household as well as industry electrical earthing requirements.
For household: Two or more Kolomite blocks connected in parallel with copper wires can be used to fulfill earthing requirements.
For industry: Kolomite powder mixed with cement is filled in a 20-ft deep borehole to form conductive concrete and connected with a Copper strip to fulfill earthing requirements.
|
Sr. # |
Kolomite |
Bentonite |
Local Earthing Materials |
|
1 |
Form: powder (graphite base) |
Form: powder (also available in rocks) |
Form: powder |
|
2 |
Resistivity: up to 0.25 Ω-m |
Resistivity: up to 2.5 Ω-m |
Resistivity: depends on solutions conc., temperature |
|
3 |
As per IEEE standard for safety deals soil treatment to lower resistivity |
Not completely as per IEEE standards |
As per IEEE standard, salt treatment must be renewed periodically |
|
4 |
Not swelling with water. |
Swells up to 13 times its dry volume with water |
Requires constant moisture |
|
5 |
Independent of water |
Depends on water to maintain its characteristics |
Dries out in absence of moisture |
|
6 |
Suitable for all environments |
Not suitable in dry environment as it can shrink away from the electrode |
Not suitable in dry environment |
|
7 |
Permanent and maintenance free |
Regular checking required |
Periodic maintenance required |
|
8 |
Maintain earth resistance with time |
Earth resistance changes with time |
Earth resistance changes with time |
|
9 |
Completely non corrosive; does not damage electrode, steel or concrete |
Corrodes carbon steel and copper structure |
earth electrode corrodes and deteriorates concrete |
|
10 |
Does not dissolve or react |
Dissolves in the earth soil |
Dissolves with water and reacts with electrode |
|
11 |
Does not pollute the earth |
Pollutes the earth |
Pollutes the earth |
|
12 |
Cost effective |
Cost prohibited |
Cost varies with materials |
|
13 |
Does not leach |
Leaches out in soil |
leaching out of the soils, eventually returning to high earth resistivity |
|
14 |
Resistivity remain constant |
Resistivity changes with time |
Resistivity increases with time |