Medium Voltage Switchgears

Construction of certified medium voltage switchboards.
• Switchboards up to 36KV / 2.500 / 25kA.
• Switchboards of motion control up to 36KV / 2.500 / 25kA.
• Control switchboards of substations

General data

General
The medium voltage switchgear for indoor use is constructed by placing standardized units side by side in a coordinated way. Construction and testing are carried out entirely in the factory. The switchgear is preset for the following apparatus:
• HD4 type gas circuit-breakers
• VD4 type vacuum circuit-breakers
• SHS2 type switch-disconnectors and isolators in gas.

Normal service conditions
The rated service characteristics are guaranteed under the following limit conditions:
• Minimum ambient temperature – 5 °C
• Maximum ambient temperature + 40 °C
• Maximum relative humidity without condensation 95%
• Altitude <1.000 m s.l.m.

Fields of application
The switchboard is used in medium voltage secondary power distribution.In particular, it can be used for transformer substations and for control and protection of feeders and power transformers.

Surface treatment
The units are made of pre-galvanized sheet. The doors of the front panels are painted grey RAL 7035. The surface appearance is semi-gloss.

Degrees of protection
• IP2X inside the switchgear
• IP3X on the external housing (operation seats excluded)
• IP2XC on operation seats.

Main bus-bars
Bus-bars are made by a bare electrolytic copper plate and are dimensioned to support the thermic and electro-dynamic stresses coming from short circuit currents.

Voltage transformers
Voltage transformers are resin insulated type and are used for supply of measures and protections. They meet standard IEC 60044-2.

Current transformers
Following applications are available:
Current sensors mounted on the breaker
Current sensors mounted in the switchboard
Ordinary CT mounted in the switchboard
Earth fault sensors

Reference standards
The switchboard is produced in compliance with IEC 62271-200 standards.
ILVIEF quality system is in compliance with ISO 9001:2008 standard

Electrical Characteristics

Rated voltage  KV 12-24-36
Test voltage (50 Hz/1 min) KV 28-50-70
Impulse withstand voltage, 1,2/50 ms KV 75-125-170
Rated frequency  Hz 50/60
Rated short-time withstand current (3s) kA 12.5-16-20-25
Rated main busbar current A 630-1250
Load break switch rated current A 630
Circuit breaker rated current A 630-1250
Outside protection degree IP 3X