It is possible to renovate and modernise existing equipment while keeping control of your investments thanks to retrofitting. You can thus extend the life of your LV switchboards while ensuring optimal safety, reliability and continuity of service of your installations without replacing all the equipment.
To guarantee a safe and efficient installation, it is important to ensure the good health of its low voltage equipment throughout its life. Continuity of service of equipment and maximum safety are crucial to limit the risk of breakdowns and accidents. This is especially true when our customers operate in a sensitive environment where production stoppages are unthinkable and emergency interventions are unacceptable.
In the long term, the question of maintaining the characteristics of the original switchboards and the modernisation of its equipment arises. Retrofitting often provides a solution for the long-term without having to replace the entire switchboard.
In the case study below, our Comeca Services teams have carried out the retrofit with a double clamp system of a first 120 series UNELEC CNP circuit breaker for one of our customers, a major player in the nuclear sector.
The final project involves the renovation of approximately 40 30-year-old NORMABLOC switchboards of type N660 with rear connection and N680 with front connection. Approximately 120 obsolete circuit breakers from the UNELEC CNP range are to be replaced. For this type of installation, seismic qualification of these new circuit breakers integrated in their columns is necessary.
Due to strict operating constraints, the work is being carried out on the switchboards in service. As with many other projects, it is not possible to completely shut down the switchboards, so the downtime must be kept to a minimum.
We have been the original manufacturer of the NORMABLOC switchboard for over 45 years. Our installed base represents more than 10,000 columns in the French nuclear sector.
For this project, our teams carried out a mechanical and electrical feasibility study (derating, current, short-circuit resistance, temperature rise) for circuit breaker ratings ranging from 1000A to 2000A.
The seismic qualification phase consisted of 3 steps:
Seismic test on NORMABLOC N687
The double clamp retrofit of a first MTZ 2 1000A circuit breaker was studied and designed to replace a CNP 1000 circuit breaker. We provided:
Once the site visit has been carried out and the preparatory meeting and site planning meeting organised (access constraints, authorisations, prevention plan), the on-site installation of this first retrofit is carried out in several stages:
As the operation requires work on switchboards in service, the risk analysis determines the protection methods to be used. Our teams therefore use suitable individual protective equipment (insulating gloves, face shields, insulating mats, insulating covers, flexible insulating blankets) during their work.
Our Comeca Service teams were able to design and implement the appropriate retrofit solution to meet all of our customer's needs.
The complete retrofit extends the life of the existing NORMABLOC switchboards without replacing the LV equipment.
Ensuring continuity of service and a maximum level of safety is achieved by renovating the equipment, but must also be complemented by rigorous maintenance and regular servicing.