Technology
High-voltage cables are used for the distribution and transmission of electrical energy.
Depending on the amount of current to be transmitted, different conductor shapes and sizes are used.
What all conductors have in common, however, is the need for a permanent electrical connection.
In practice, screw connectors are increasingly being used for this purpose.
Due to the variety of conductor designs, these must be individually adapted from a certain cross-section.
This is the only way to ensure an electrically and mechanically reliable connection that meets the requirements of permanent current transmission.
Key design features
All our products are designed to maintain a permanently low transfer resistance throughout the entire service life of the connected cable.
By observing the following design principles, we ensure that the thermal stability of the electrical connection is guaranteed under all operating and environmental conditions.
Body construction
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Material: Aluminium alloy with increased conductivity and enhanced mechanical strength
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Minimum length: Sufficient to fulfil the mechanical and current transfer requirements (mainly depending on number of bolts required for electrical contact and tensile strength)
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Maximum length: Depending on the cable accessory
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Outer diameter: According to XLPE cable insulation
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Inner diameter: Adapted to conductor type and diameter
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Inner surface: Transverse grooves for defined line contacts
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Wall thickness: Must be neither too thick (sufficient elasticity to handle thermal cycles) nor too thin (minimum required thread length)
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Surface treatment: Tin-plated or silver-plated depending on the application
Body of RAC JC-3000 for 550kV cable joint application
Shear bolt layout
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The number, size and arrangement of shear bolts is crucial for optimising the contact pressure of the conductor
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Pressure per bolt is limited because of mechanical strength of thread and reduction of tensile strength by too high pressure force
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Homogeneous deformation of conductor must be ensured
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No main current path through bolts
