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Contactors and switches.need help urgently


New Member
Hi, i have 3 contactors and a 4 way switch.
In position 1 of the switch i need contactor 1 to close.
In position 2 i need contactor 1 and 2 to close
In position 3 i need contactor 2 to close
And position 4 i need contactor 1 and 3 to close.

Can someone please make a drawing of how i can achieve this please with relays.

Thank you


Well-Known Member
Most Helpful Member
Use one relay per contactor.

Power the relays from the switch, eg. switch common to +DC and relay common to -DC / 0V of whatever supply the relays work on.
Connect the switch output contacts via diodes to the relay coils that need to operate in each switch position.

This is a more complex version but illustrates the principle - each switch position can feed any combination of relays as needed, via diodes in the appropriate locations.
(Called a "diode matrix" system).


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