I need an on off switch to switch between 2 relays. For example, switch is off relay 1 has power , switch on relay 2 has power

 

Buy a SPDT toggle switch

 

Wish i could. That would be easy. Customer is needing this specific switch do to specific looks for vintage application

 

What is the nature of the vintage application?

 

What is the nature of the vintage application?

Fuel system in vintage truck

 

https://www.tractorsupply.com/tsc/p...on-fuel-tank-selector-switch-fbhk-sta-ds-2430

 

That is the switch, I need to wire it to two relays the way described above

 

Is your question how to wire up that switch?

 

Yes

 

Try this:

 

You can wire the power for the second relay using the normally closed contact on the first relay. That way, when relay is off, relay 2 is on—and when relay one is turned on by the switch, it turns off relay 2.

 

You can wire the power for the second relay using the normally closed contact on the first relay. That way, when relay is off, relay 2 is on—and when relay one is turned on by the switch, it turns off relay 2.

How

 

The same way you wire a switch to operate the relay. Route power for relay 2 through the common and NC (Normally Closed). THe NC contacts are closed when there is no power to the relay and open when the relay is energized.

So the default for the switch is relay 2 on. That is, relay 2 will turn off when the switch is turned on and relay 1’s coil is energized.

But, be sure you recognize that no matter what scheme you use, relay 2 will constantly draw power unless you switch it off some other way (ignition, etc.).

 

Technically with a 5 pin relay only one is needed unless you need more contacts.

 

Technically with a 5 pin relay only one is needed unless you need more contacts.
View attachment 307615

I assumed the relays were preexisting but if not and there is no issue with current handling, it‘s the same scheme I described above without relay 2, which is better because there is no current draw that way.

 

I assumed the relays were preexisting but if not and there is no issue with current handling, it‘s the same scheme I described above without relay 2, which is better because there is no current draw that way.

Thank you so much, I just had a hand to face moment, thank you