|In some substations, the switchgear is obsolete and had been operating for more than 30 years and has no security features required (cells without interlock ) . In such situations the installation of new equipment provides us with all the necessary security to ensure safety of workers and are equipped with devices that makes possible:
- Automatic selection of affected sections of faulted lines, while correlated with those of protection relays installed in the power stations, on feeders
- Remote operated ( from dispatch ) , connecting and disconnecting new breakers that are to be installed
- Remote transmission of vital data, for the efficiency and status of the components present in the substations ( e.g. position of circuit breakers , battery efficiency , unauthorized acces, etc. . )
Modernization of medium voltage cells of the substation has major implications in increasing the reliability of installations, offers the possibility of including these substations in the SCADA system and ensure safety in operating, with lower maintenance ( such cells do not require scheduled maintenance ). The new cells that are installed in the substation have a high perfomance , modular switchgear with SF6 breaker or vacuum , etc. . All new cells that are installed are designed for 24kV voltage can be set to 24 VDC motorization , depending on requirements .
The works to be executed shall include all operations necessary for the dismantlement of existing cells , cables , columns , walls, achieving layouts during execution , cross cabling , safety measures , etc. . Installing and connecting the new cells into the medium voltage grid include: making the necessary cable channels , covering the remaining floor space with corrugated sheet , connecting the cables with the switch-gear , restoring damaged lighting installations , rehabilitating the 20kV chamber and the low-voltage chamber and other repairs.