BE has a wide variety of services that can assist in the design,
construction, or troubleshooting of problems at power substations or other
sites with a ground mat.
1. Resistivity is a measurement
of the ability of the earth to conduct electricity. This value is
essential in substation design considerations as well as the provisioning of
communication services into the substations. BE measures this value at multiple
(10 or more) probe spacing then using standard mathematical algorithms evaluates
these measurements as a two-layer model of soil resistivity.
2. Ground resistance measurements of a
newly constructed ground grid are essential to any electronics installation
that is exposed to the influences of lightning. Standard methods for
measurement of the resistance of a new earthing electrode system incorporate
the usual “fall-of-potential” measurement that can be accomplished with the
"garden-variety” Megger. However, once the ground grid has seasoned,
the resistance will change. Sometimes the change is higher and sometimes
it is lower, but the resistance of the grid is not a constant over time.
Seasonal variations occur, as well, which affect the performance of the
ground grid, such that it may be beneficial to make repeated measurements of
the grid over time in order to validate the effectiveness of the grid.
3. The measurement of an existing grid cannot be accomplished with the standard Megger. The only
device that can actually measure the resistance of a working ground grid is the
Smart-Ground Multimeter (SGM).
4. The location of the ground grid elements is always vital knowledge and frequently unknown.
Particularly for older substations which have changed ownership and
original drawings have been lost and no longer exist, the reconstruction of the
drawings can be very beneficial particularly if the site is being expanded or
updated. BE can identify the location of
these grid elements and provide CAD drawings (.dwg, .dxf, .pdf) of the grid as
it is currently constituted.
5. Point-to-point continuity measurements are often helpful. The effectiveness of the ground grid can
frequently come into question, particularly with older grids. The SGM is
the ideal tool for determining the efficacy of an existing grid, as it will
provide, not only the impedance of the connection, but also the phase angle of
the connection which can confirm if the elements are bonded metallically or
simply through the earth.
6. Touch and step potential measurements are very helpful when investigating safety concerns at a
substation. The safety of personnel working within a substation at a
metering cabinet or operation a mechanical switch can be called into question
during critical operations. The SGM can actually measure the touch
potential and step potential at specific locations within a substation.