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GENERAL INSTRUCTIONS FOR
CMS-17
SWITCHING AND BREAKING SUBSTATION
IG-178-GB
version 01
11.08.2011
3.4. LEVELLING PROCESS
For the correct assembly of the enclosure, the ground levelling is important.
The following equipment is recommended for correct levelling:
A spirit level
A square-end spade
Levelling tools
A 100 mm thick compacted and levelled layer of sand is required at the bottom of the
excavation in order to prevent differential settlements.
The installation operation consists of positioning the
CMS-17
in the excavation made for this
purpose and of connecting the MV cables, along with the external earthing network.
3.5. EARTH CONNECTION
The
CMS-17
Switching and Breaking Substation has an internal earthing circuit to facilitate
the connection of the different elements to the earthing network external to the Switching and
Breaking Substation.
3.5.1. Protective Earth Connection
For the correct connection of the protective earth (metallic parts), the enclosure of the
CMS-17
Switching and Breaking Substation has a switching box located on the inside of the
left side wall, which is accessible from the outside through the doors.
The MV switchgear unit earthing is routed to this connection point, which connects all the
earth connections of all the concrete enclosure's electrical equipment.
CAUTION:
Consult
Ormazabal’s
Technical-Commercial Department in the event of installation on a
slope.
