Gas insulated switchgears

Kaldera medium-voltage gas-insulated metal-enclosed switchgear 8DJH (ring main units)

This switchgear type is produced in workshops of Kaldera company under Siemens licence

Main Features

Gas insulated switchgear with a vacuum circuit-breaker up to 40.5kV/40kA(3s)/2500A Single and double busbars Supply continuity of 2A Resistance to internal arc 40kA

Benefits for Users

High level of personnel and equipment safety, simple handling Safe for the environment – no contact with gas during installation Various types of cable connections, Integrated equipment protection system Regardless of whether you manufacture, distribute or only use the electricity, the contemporary economic situation imposes the need for a favorable solution that will at the same time be reliable, safe and easy to use. The range of the medium voltage cells for application in electricity distribution meets all the requirements, from the simplest to the most demanding processes. This switchgear is highly reliable and suitable for application in power utility and industrial networks, power plants and infrastructure facilities. This switchgear has been designed for voltages up to 24kV and can be fitted with circuit-breakers or contactors, both the vacuum and the SF6 gas.


This switchgear has been type-tested under the IEC 62271-200 and defined as:
  • PM – switchgear divided by metal partitions and shutters into segregated compartments
  • Service continuity LSC 2B
  • Internal arc class AFL(R)

  • Safety

    These switchgears have been designed to ensure operator safety and service continuity. The cells are accessed from the front and all operations are performed while compartment doors are closed. A system of mechanical blockages prevents operator’s faults and disables insertion of the lever unless it is completely safe to do so.

    Technical characteristics
    Rated voltage 24.0 kV
    Operating voltage 20.0 kV
    Rated short-duration power-frequency withstand voltage 50 kV
    Rated lightning impulse withstand voltage 125 kV
    Rated frequency 50 Hz
    Short circuiz current
    Rated short-time withstand current Ik 16.0 kA
    Rated duration of short-circuit 1 s
    Rated peak withstand current Ip 40 kA
    Rated current
    Rated busbar current 630 A
    Height (without absorber pressure, low section) 1400 mm
    The depth of the cell (the default) 775 mm
    Depending on the assigned typical and different versions of cable connections,cell depth can be > 775 mm
    Distance of the side wall ≥ 50 mm
    SpecificationText217 ≥ 200 mm
    Distance rear wall for wall mounting ≥ 15 mm
    The width of the control passage (depending on national specifications)
    Recommended for Germany ≥ 800 mm
    Recommended for an extension or replacement plates ≥ 1000 mm
    The depth of the cable basement or cable trench (according to the bending radius of the cables) ≥ 600 mm
    Attachment with the switchgear
    Partitions category PM
    Gas insolated switchgear degree of protection IP 2X
    Switchgear hausing degree of protection IP65