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11.08.2011
IG-178-GB
version 01
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GENERAL INSTRUCTIONS FOR
CMS-17
SWITCHING AND BREAKING SUBSTATION
3.3. EXCAVATION DIMENSIONS
For the installation of the
CMS-17
Switching and Breaking Substation, an excavation
including an earthing loop is necessary.
In order to carry this out, it is recommended that the minimum construction worksite safety and
health Regulations be observed. Among others:
Before beginning to open, carry out a preliminary study of the ground for the purpose of
knowing its stability and the possible existence of conduits.
Avoid accumulating excavated material and equipment next to the edge of the
excavation, taking the necessary precautions to prevent the walls from caving in and
materials falling inside.
As a general rule, maintain a 3000 mm area around the excavation free of materials and
vehicle traffic.
In the case of rain and puddles, carefully inspect the excavation using qualified
technicians before resuming the work. Carry out immediate pumping out of water that
may be present inside the excavation in order to prevent the stability of the slope from
being altered.
The operators that work inside the excavation must be properly trained and informed and
must use a safety hat as well as the appropriate protective clothing for each specific
hazard.
Ensure that the building is not buried over the reference line marked on the walls of the
concrete enclosure. The maximum burying height is 480 mm measured from the base.
The measurements below must be adapted in each case, depending on the solution adopted
for the earthing network according to the earthing diagram.
3.1: Excavation dimensions
Dimensions in millimetres
1770
2550
480
100
