200 volts DC to 12 volts DC converter question?

Offroader

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This is for my hybrid car to power a dash cam when I'm not using the car.

My battery voltage range is between 176 and 210 volts DC.

Would I be able to use an AC 100-240V DC power adapter to 12 volts?

Basically something like this, but its rated for AC, I heard it will work but I just wanted to make sure. Thanks.

https://www.ebay.com/itm/AC-DC-100-240V-To-12V-2A-Buck-Converter-Isolated-Step-Down-Power-Supply-Board/263059583787

Will I be able to just use any AC-DC converter that is used for stuff like notebooks or electronics. to power the dash cam, if its rated for 100-240 volts AC?
 
Probably. Worth a shot to try it if you already have a cheap wallwart laying around for the purpose. If you have to buy something, you might as well get a part designed for it, though.

Whether a wallwart will work depends partly on the voltage ratings of the parts in the converter. IIRC, numerically AC converts to DC by dividing the AC by 1.4, so DC should convert to AC by mulitplying the same. Means that 200 x 1.4 is 280, so the converter parts should be rated for up to 280-300vac input.

Mostly it's the diodes and caps, on the input side, though there might be other parts.

Not all wallwarts will start on DC; some require AC input to function, regardless of teh input voltage itself. (even with switching supplies, SMPS).
 
Offroader said:
Would I be able to use an AC 100-240V DC power adapter to 12 volts?

Will I be able to just use any AC-DC converter that is used for stuff like notebooks or electronics. to power the dash cam, if its rated for 100-240 volts AC?
Yep and yep. The usual problem is getting these switcher supplies to start at substantially lower than 100VDC and you're way above that, so should be fine.

I would recommend a standard wall wart since they're already packaged and pretty weatherproof from the gitgo.

FWIW: Realize that automotive stuff normally expects to see 13.8V or more but will run reliably in the range 11V-16V. The notable semi-exception is lighting which is quite a bit dimmer at only 12V. 15V laptop supplies are a good choice if you want to run lights (ebikes), but in this case a more readily available 12V adapter is okay since you are just powering an electronic thingie with its own internal regulator.
 
Offroader said:
Would I be able to use an AC 100-240V DC power adapter to 12 volts?
Usually. If you want to be on the safe side, some of the smaller Meanwell supplies are actually rated to work with DC input. The LRS-35, for example, works from 120-373VDC. You can even get the 15V version and dial it back to 13.8 volts to simulate the vehicle power bus more precisely.
 
90% of AC stuff with rectification works with DC. but 220V AC becomes over 300V DC so the device needs a high DC voltage in order to trigger the conversion IC to work.

most regular AC stuff works fine from 80~90VDC. i use a 90V DC battery made from AA cells to power my scope when i am mobile. :mrgreen:
 
Thanks guys, I'm just about to actually hook this up to see if it will work.

Quick question. The DC/DC power supply has 3 prongs for AC. Which would be Line / Neutral / Ground.

How would you connect the 3 prongs to a DC battery?

Thanks.
 
Offroader said:
Thanks guys, I'm just about to actually hook this up to see if it will work.

Quick question. The DC/DC power supply has 3 prongs for AC. Which would be Line / Neutral / Ground.

How would you connect the 3 prongs to a DC battery?
Neutral to -, line to +. You can connect ground to ground if you like.
 
billvon said:
Offroader said:
Thanks guys, I'm just about to actually hook this up to see if it will work.

Quick question. The DC/DC power supply has 3 prongs for AC. Which would be Line / Neutral / Ground.

How would you connect the 3 prongs to a DC battery?
Neutral to -, line to +. You can connect ground to ground if you like.

Thanks worked perfectly. I actually used a Meanwell LRS-50, like you suggested. Now i can plug in AC or DC voltage from my 200 volt hybrid battery.

Would you recommend I use any fuses on the high voltage line to the Meanwell LRS-50?
 
The Meanwell should already have a fuse inside it somewhere, but not DC rated. It wouldn't hurt to have a DC rated fuse or solar circuit breaker on the input.

I would recommend against connecting the ground input to either of the battery lines but it could be connected to the chassis of the car.
 
Does the car have a constant 12v supply already in the factory harness in the dash?

If it does it would easier to tap into that.
 
Offroader said:
Would you recommend I use any fuses on the high voltage line to the Meanwell LRS-50?
I would use a DC rated breaker to have the ability to turn it off and on, but a fuse (also DC rated) is a reasonable option too.
 
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