A general converter question

[sixbennetts]

I bought a 24 volt to 12 volt converter. It has 24 volt in switched, 24 volt in from battery, (non-switched), and ground in. Output side has 12 volt switched, 12 constant, and ground.

My stereo requires switched 12 volt only. Doesn't need constant power. Can I just use the switched leads on the converter or do I have to run leads to the battery too?

[TechMOGogy]

Use the 12v leads off the converter
Never run to battery

[undysworld]

Didn't it come with an operator's manual??!? Where you buyin' this stuff?? (Don't let Vince hear that you're buying Chinese made junk... ) Without knowing the operation of the converter, it's hard to say. Obviously the radio doesn't care where it gets power from.

Here's my guess: The 24V switched input, when turned on and off, will control the 12V Switched output. So if the radio were attached at 12V Sw. Output, and the power to the 24V Sw. Input was turned on and off, the power to that radio would likewise turn on and off.

[sixbennetts]

That's what I figured, guys. Just wasn't sure if the unswitched lines had to be used also for it to work. I'll try just using the switched lines. It was getting late, didn't get it to work. I probably didn't jump off a hot fuse terminal.

(This was a gift from a well-meaning son, I kinda have to use it. I also want to make it work).

[TechMOGogy]

Just test the 12v wires with a meter before you hook up the radio.
Good luck with it (note: most converters are very similar in the way they work - I am sure Google will help you find a pdf manual if not for yours then for a similar one you could use as a reference)
Dan

[sixbennetts]

Thanks, Dan. Don't have a meter so we're doing it the old trial and error method. Maybe tomorrow, though, when I'm stronger. Chemo kicked my a$$ today.

Thanks all, I'm sure we'll get 'er working.

[undysworld]

Sixbenetts,

Hope you're back on your feet again soon.

Hey, send one of those well-intentioned sons out to Harbor Freight and pick up one of these: http://www.harborfreight.com/7-function ... 92020.html

It's only $4.99, and it would allow you to do simple tests like this way easier than actually connecting the device to see what happens. Plus, it's way cheaper than hooking something up wrong and smoking something.

[sixbennetts]

Thanks! Don't have a Harbor Freight here, but I can order it online easy enough. Only $4.99, huh? Are you sure it's not cheap Chinese junk? (I don't want Vince to yell at me!

[undysworld]

Yup, I'm afraid it is. I have to admit to an occasional transgression myself. Hard to avoid these days. Let's say: I try.

And I'm sure this meter will have limitations. But it should work for basic circuit testing.

[audiocontr]

The only way to make the memory/constant 12v work for the stereo purpose is to power the inverter constantly. I would not recommend it if you go days between driving. You'll drain the batteries from the constant draw. You will have to deal with the scenario that the stereo will lose power when you turn off the truck, or add some sort of charger (solar)

You could use a small 12v battery to maintain the memory, but now we are getting pretty complex due to the need for a charging circuit.



This may be one of those scenarios where a large resistor is most beneficial. Wonder what the draw would be then?

[undysworld]

The only way to make the memory/constant 12v work for the stereo purpose is to power the inverter constantly.

While true, I'm not sure where this idea arose in this application. He wrote in his original post that he did not need a memory circuit for the stereo:

My stereo requires switched 12 volt only. Doesn't need constant power.

No sense making it more complicated than is needed.

[sixbennetts]

Yeah, instructions call for switched ACC only, not constant hot, so it must have some sort of power storage. It's a remote faceplate, so there's probably a small battery in it. Thanks for the heads up though. I'm holding off completing the install until the multimeter gets here so I can do it right.

[audiocontr]

The only way to make the memory/constant 12v work for the stereo purpose is to power the inverter constantly.

While true, I'm not sure where this idea arose in this application. He wrote in his original post that he did not need a memory circuit for the stereo:

My stereo requires switched 12 volt only. Doesn't need constant power.

No sense making it more complicated than is needed.

Totally missed that part. My apologies.

[sixbennetts]

None necessary, buddy. I welcome your input.