• C801 optimised to meet the requirements of 800V vehicles
• Shock resistant up to 120g/20ms thanks to patented interlock system

Although invisible, they play a key role in both vehicle and occupant safety: contactors in the junction box of electric vehicles. 400V battery banks are wide-spread, and are perfectly matched to the 400V charging points that are currently in use. However, in order to make e-mobility compatible with long journeys and large vehicles, the automotive industry’s number one priority is 800V vehicles. These are equipped with two 400V battery banks, which are connected in parallel when charging but in series when driving so that 800V is available. As a result of this dual requirement, the junction box of 800V vehicles requires additional contactors in comparison with 400V vehicles. These are then set inactive in driving mode and active in charging mode.
“When driving, the contacts are open”, explains Günther Rott, Director Business Development Automotive of Schaltbau GmbH. “Therefore, it is important that the contactor does not close uncontrollably even under high mechanical loads, as may occur during an accident. Were this to happen, the consequence would be a short circuit that would destroy the junction box and probably also the vehicle.” Therefore, the C801 contactor from Schaltbau, which is specially de-signed to meet the requirements of 800V vehicles, has a patented mechanical interlock system that prevents the contacts from closing even if extreme shocks of up to 120g/20ms occur.

Continuous current up to 250 A and high energy efficiency

The compact C801 interlock contactor has a structure that is matched to the usual installation geometries inside an electric vehicle. Thanks to the generously dimensioned air gaps in the contact area, the rated insulation voltage is 1,000 V. During operation, thanks to high contact forces and optimised contact geometry, a thermal continuous current of up to 250 A can be withstood, while the short-time withstand current is up to 16,000 A. During use, the contactors are only activated when charging at 400V charging points and do not consume any power either when driving or charging at an 800V charging point. This reduces the vehicle’s power consumption and prevents additional heat in the junction box.
“With these technical specifications, our C801 interlock contactor is perfectly suited to premium cars with 800V systems. However, as powerful batteries are also crucial for commercial vehicles and buses, and the demand for high-range mid-size vehicles is also increasing rapidly, interlock contactors intended specifically for these applications are already prepared for series production,” says automotive expert Günther Rott, whose aim is to permanently establish Schaltbau as a supplier to the electromobility sector.

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