12v switched source

[Machineryrepairman]

I have a 2017 Chevy express and I want to install a DC2DC charger. I need a switched source to turn it on. What fuse would be recommended? I know how to identify switched fuses. I was just wondering if anyone had done this and what one they used?
Has anyone just installed a switch on a constant circuit?  I would forget to turn it off. What are your thoughts on using a 12v plug to plug the trigger wire into the accessory outlet?

 

[Sofisintown]

In a video a while ago I saw them using the radio fuse to power a continuous duty solenoid that turns the switch on and off.
The radio operates only when the key is turned to the on position, therefore the power transfer stops if the ignition is off.

 

[Machineryrepairman]

Thanks unfortunately there are a few retained power accessory and the radio is one.
I have yet to check under the hood. I was trying to keep it to the box under the seat.

 

[Sofisintown]

well then, the fuel pump fuse will do. the pump works only when the car runs.
You can't forget that...

 

[highdesertranger]

with todays computer controlled vehicles I would not tap into any critical power supply.

the radio should have 2 hot wires, 1 hot all the time and one hot with the key in the run and accessory position. sometime the accessory port/cigarette lighter is only on in the run position sometimes it is hot all the time.

some vehicles actually have a place on the fuse panel that is made just for what you describe, some don't. I know the older Chevys had those taps on the fuse panel I don't know about yours.

highdesertranger

 

[Weight]

This is why the first thing to buy for your electrical system is a multi-meter. Preferably one that reads dc amps as well as volts. This one is a good deal. https://shop.marinehowto.com/products/sterling-power-dc-ac-amp-clamp-volt-meter