Schaltbau, a supplier of safety components for DC systems, has designed contactors to meet the charging and driving requirements of 800-volt EVs, which are equipped with two 400-volt battery banks.
The C801 interlock contactor is compact and designed to fit the usual installation geometries inside an EV. The contact area has substantial air gaps, allowing for an insulation voltage of 1,000 V. Due to strong contact forces and optimized contact geometry, the contactor can withstand a thermal continuous current of 250 A and a short-time withstand current of 16,000 A during operation.
The contactors only operate while charging at 400 V charging stations and do not consume power or generate heat when driving or charging at 800 V. The contactor includes a proprietary mechanical interlock system that keeps the connections from closing even if there are extreme shocks of up to 120 g per 20 ms. Schaltbau is also preparing to produce interlock contactors to meet increasing demand for high-range mid-size vehicles as well as commercial vehicles and buses.
“When driving, the contacts are open,” explains Günther Rott, Director Business Development Automotive of Schaltbau. “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.”