ARA series expandable alternating relays from the ATC Diversified Electronics Division of Marsh Bellofram are designed for use in multiple load installations that are required to alternate in sequence and have the ability to accept an additional load installation in the future.
ARA-120-AME: the ARA-120-AME is a duplexer/triplexer alternating relay. With the selector switch in position A, this alternating relay will duplex the loads on terminals 7 and 9. With the switch in position B, the alternating relay will triplex the three loads on terminals 7, 9 and 11. For automatic alternations, a factory-installed jumper is in place between terminals 3 and 4. The alternating action is accomplished when the control switch between terminals 2 and 4 opens. For external clocking alternations, remove the factory installed jumper between terminals 3 and 4 and place an isolated normally open switch between terminals 2 and 3. The alternating action will occur each time this isolated switch is closed and then re-opened. ARA-120-ANE: The ARA-120-ANE is a triplexer/quadraplexer alternating relay. With the selector switch in position A, the alternating relay will triplex between the loads on terminals 7, 8 and 9. With the switch in position B, the alternating relay will quadraplex the loads on terminals 7, 8, 9 and 10.