Main controlled: Change on removal of supply:
The relay is initially in any state, on or off, apply supply voltage. The relay keeps in state. Remove the supply voltage. The relay will now change state and will keep its state without the supply. Apply & remove the supply again for the next change in state.
Mains controlled: Change on application of supply.
Link pins 5 and 7 (Link A). Apply supply voltage. The relay changes state. Remove supply. The relay keeps its state.
Pulse controlled. Link pins 6 and 7 (Link B). The relay is initially in any state, apply and supply voltage. The relay keeps its state. When the contact between pins 5 & 7 closes, the relay will change state. Remove the supply voltage. The relay will keep its state without the supply. Minimum time supply connected for relay to react: 1 second.
