DC switching relays designed for powertrains now in distribution

February 09, 2015 // By Christoph Hammerschmidt
The electrification of powertrains arouses electronics designers' interest in a species of components that many already believed obsolete: Relays, in particular those to switch high voltages. Panasonic Electric Works supports the trend towards electric powertrains with products that take into account a broad range of powertrain types for passenger and commercial vehicles: hybrid, plug-in hybrid, pure electric vehicle and fuel cell. These relays now are also available from component distributor TTI.

Beside the main and precharge relays, pure electric vehicles are usually equipped with a DC charging interface. For this application and other functions, Panasonic has developed EV relays in different shapes from a nominal 10A up to a maximum of 300A.  Switching capacity of the EV relay family is up to 2500A, 300VDC. Compact and robust, Panasonic EV Relays have a patented, hermetically sealed ceramic capsule construction that contains the contacts. These contact chambers are filled with hydrogen gas, which is a better conductor of heat than air or nitrogen and dissipates the enormous heat generated by the arc very efficiently, resulting in higher switching performance.  An added benefit is that it also prevents the contacts from oxidising. The ceramic chamber separates the arc electrically and thermally from other components and provides enhanced safety when shutting off high DC voltages.    

One of the most popular products in Panasonic’s EV relay product family is the AEV14012, a 120A relay which can be used up to a system voltage of 450VDC. Nominal switching capacity is 120A 400VDC and maximum carrying current 120A (continuous).  Physical dimensions are 75mm x 40mm x 79mm and the unit weighs 400g. This specification suits most applications for hybrid and electric vehicles as it allows strong acceleration and good overall performance at an attractive price point.

For more information about TTI, visit www.ttieurope.com.