At Arc Components Limited there are many 12V changeover switch relay options, from standard automotive 12 volt dc changeover car relays, to unique caravan, truck, van, boat and marine application power line switch relays. The range covers most style vehicle electric relays including versions with sealed resistors and diodes.
What is a changeover relay? You can have a variation with some 12V changeover relay configurations (latching, suppressed, etc.) but a standard 12V change-over relay is a switch-over function in a power line (pins usually designated 30, 87 and 87a), that switches circuit (from 87 to 87a) when the internal coil is energised (pins usually designated 85 and 86). Commonly used for switching a positive line from one 'on' position to another (for example; dipped beam to high beam) and commonly five pin or terminal.