ALTERNATING RELAYS Typical Installations Typical Installations Duplex DPDT Cross-Wired In the off state, both the LEAD Switch and the LAG Switch are open, the Alternating Relay is in the LOAD 1 position, and both LOAD 1 & LOAD 2 are off. The red LED marked “LOAD 1” is ON. When the LEAD Switch closes, it energizes LOAD 1. As long as the LEAD Switch remains closed, LOAD 1 remains energized. If the LAG Switch closes, it energizes LOAD 2. When the LAG Switch opens, LOAD 2 is turned off. When the LEAD Switch opens, LOAD 1 is turned off and the Alternating Relay toggles to the LOAD 2 position. The red LED marked “LOAD 2” is ON. When the LEAD Switch closes, it turns on LOAD 2. If the LAG Switch closes, it will energize LOAD 1. When the LAG Switch opens, LOAD 1 is turned off. When the LEAD Switch opens, LOAD 2 is turned off, the Alternating Relay toggles back to the LOAD 1 position, the red LED marked “LOAD 1” is ON, and the process can be repeated. NOTE: the LEAD switch must always close before the LAG switch and must always open after the LAG switch. The diagram at right illustrates a type of operation known as “Sequence On - Simultaneously Off (S.O.S.O.)”-the two loads are energized sequentially, but remain on together until the OFF switch is opened. In the initial OFF state, all three switches are open, the Alternating Relay is in the LOAD 1 position, and both loads are off. No action happens with the Alternating Relay or either load when the OFF Switch closes. When the LEAD Switch closes, Load M1 turns on. When the LAG Switch closes, Load M2 turns on. Both loads remain on as long as all three switches are closed. When the LAG Switch opens, Load M2 remains on because the OFF Switch is still closed. When the LEAD Switch opens, Load M1 remains on because the OFF Switch is still closed. When the OFF Switch opens, both Load M1 and Load M2 are turned off simultaneously. The Alternating Relay toggles to the LOAD 2 position. The entire cycle is then repeated, but with Load M2 energized first followed by Load M1. NOTE: Both drawings shown are for DPDT Cross-Wired units with input voltage connected to Pins 3 & 6. For DPDT Cross-Wired units with input voltage connected to Pins 5 & 6, visit www. macromatic.com/ar-apps. Triplexor All three switches are open and all loads are off. When the LEAD Switch closes, it energizes LOAD 1. As long as the LEAD Switch remains closed, LOAD 1 remains energized. If the LAG Switch closes, LOAD 2 is energized. If the LAG2 Switch closes, it energizes LOAD 3. Each load is turned off in sequence as the switches are opened. The entire cycle is then repeated, but with LOAD 2 energized first followed by LOAD 3 and then LOAD 1. NOTE: Power for outputs is supplied from L connection, not through input switches. Drawing references terminal numbers on 8 pin products 800.238.7474 | www.macromatic.com | [email protected] 3 alternating relays | installation
