Technological characteristics
From Electrical Installation Guide
MV & LV architecture selection guide
Technological characteristics
The technological solutions considered concern the various types of MV and LV equipment, as well as Busbar Trunking Systems .
The choice of technological solutions is made following the choice of single-line diagram and according to characteristics given below.
Environment, atmosphere
A notion taking account of all of the environmental constraints (average ambient temperature, altitude, humidity, corrosion, dust, impact, etc.) and bringing together protection indexes IP and IK.
Different categories:
- Standard: no particular environmental constraints
- Enhanced: severe environment, several environmental parameters generate important constraints for the installed equipment
- Specific: atypical environment, requiring special enhancements
Service Index
The service index (IS) is a value that allows us to characterize an LV switchboard according to user requirements in terms of operation, maintenance, and scalability.
The different index values are indicated in the following table (Fig D4):
| Operation (setting, measurement, locking, padlocking) | Maintenance (cleaning, checking, testing, repaining) | Upgrade (addition, modification, site expansion)z | |
| Level 1 | IS = 1 • • Operation may lead to complete stoppage of the switchboard |
IS = • 1 • Operation may lead to complete stoppage of the switchboard |
IS = • • 1 Operation may lead to complete stoppage of the switchboard |
| Level 2 | IS = 2 • • Operation may lead to stoppage of only the functional unit |
IS = • 2 • Operation may lead to stoppage of only the functional unit, with work on connections |
IS = • • 2 Operation may lead to stoppage of only the functional unit, with functional units provided for back-up |
| Level 3 | IS = 3 • • Operation may lead to stoppage of the power of the functional unit only |
IS = • 3 • Operation may lead to stoppage of only the functional unit, without work on connections |
IS = • • 3 Operation may lead to stoppage of only the functional unit, with total freedom in terms of upgrade |
