Schunk supplies 123 depot charging pantographs to King County Metro in Seattle

King County Metro has received 123 inverted pantographs from Schunk Transit Solutions for electric bus charging at its Tukwila Base depot.

The installation, reported by US specialized media Mass Transit, concerns charging infrastructure designed for battery-electric buses operating in the Seattle area. Full commissioning of the new system equipped with Schunk pantographs is scheduled for spring 2026

Schunk pantographs installed at King County Metro’s Tukwila Base

The equipment is based on the SLS 201 series and is integrated into the charging infrastructure rather than mounted on the vehicle roof.

King County Metro operates approximately 1,200 buses in Seattle. Its fleet includes around 1,100 hybrid battery-diesel buses and more than 300 fully electric vehicles, according to figures reported by Mass Transit.

During a pilot phase with six SLS 201 pantographs, Schunk Smart Charging was tested under operating conditions. The reported results included no power interruptions linked to vehicle movement or high humidity.

The inverted SLS 201 pantograph lowers from the charging structure and connects with High Power Charge Rails mounted on the bus roof. Electricity is transferred by direct current from the infrastructure to the vehicle battery.

The system is designed for depot use and for opportunity charging at stops along the route. Schunk states that batteries can be recharged within minutes.

The pantograph uses a spring-and-drive system and four separate roof charging rails to maintain contact during charging.

Schunk Transit Systems manufactures the pantographs at its US facility in Wisconsin. The company says the equipment meets Buy America requirements and is labelled and certified according to US safety standards. The contract with King County Metro also includes commissioning support, maintenance and technical training.