Heliox, a Siemens business, is partnering with King County Metro in Washington state to pilot the new Heliox Flex Pro 480-kW charger as part of the agency’s electric bus infrastructure modernization efforts.

King County Metro serves Seattle and 34 surrounding cities, operating buses, trolleys, paratransit, vanpools, water taxis, streetcars, and regional transit services. The agency is testing the charging system to evaluate new charging technologies for battery-electric bus operations.

The Heliox Flex Pro charger has a compact 12-square-foot footprint and supports overhead pantograph charging.

The charger can support either rapid opportunity charging through a high-power pantograph or off-shift depot charging with up to six pantographs or plug-in dispensers connected to a single system.

The system supports CCS1 charging configurations at 250 amps and inverted pantograph charging at either 250 amps or 600 amps. Heliox said the charger is compatible with multiple bus OEMs and current charging standards.

Flex Pro distributes power in 80-kW increments across up to six outlets and can charge up to six vehicles simultaneously. Agencies can select either dynamic power sharing, which adjusts power allocation among chargers in real time, or static power sharing, which maintains fixed output levels.

The cabinet design requires front-only access for installation and maintenance. The system supports dispenser-to-cabinet distances of up to 328 feet, or up to 984 feet with chained connections, allowing flexibility in depot layouts.

Heliox said the charger is backward-compatible with existing Flex dispensers and uses a modular architecture designed to maintain reduced charging capability if a single power module fails.

The Flex Pro charger is available in both Build America, Buy America-compliant and non-compliant configurations and includes a 24-month warranty and preventative maintenance options.