Lead Exit Systems
WEIDMANN offers a variety of lead exit systems which form shielded barrier systems to lead conductors through tank walls from the winding to the bushing or tap changer.
Field of Application
Lead exit systems are used mainly in power transformers of high voltage. The range starts from 220 kV up to 1200 kV AC or in HVDC applications up to 800 kV according to WEIDMANN’s design criteria.
A Barrierboard forms a drip-proof partition between the core and coil assembly and the tap changers. Barrierboards are manufactured from laminated Transformerboard TIV of the thickness appropriate for the size and pressure applied. WEIDMANN offers several kinds of connectors depending on the needs. As an additional service WEIDMANN can perform a hydraulic pressure test to measure deflection.
A Faltenbalg is a special WEIDMANN component that separates the lead exit turret from the tank of power transformers. This offers not only protection for the winding but also the possibility of separating the tank and turrets during transportation. The design of Faltenbalgs must take the field conditon of AC or DC application into consideration. Depending on the requirement the design is pressure tested up to 2.5 bar. As an additional service WEIDMANN can perform a hydraulic pressure test to measure leakage and deflection.
Lead exits are supplied not only in a cost efficient and reliable modular version for 400 kV or 500 kV but also in customized designs for higher voltages up to 1200 kV or even for HVDC. As a business partner WEIDMANN may take responsibility not only for manufacturing but also for field studies and design. The standard design is based on a metallic core insulated with shaped Transformerboard. A number of barriers depending on the design voltage subdivide the oil gap between base insulation and tankwall. The result of our design is a minimized size of the turret at maximum safety.
Planned changes of service voltages or usage at different sites are occasionally reasons for specifying transformers with dual voltage. WEIDMANN offers several kinds of connectors depending on the needs.