Any electronics guys in here? - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


Lounge For casual talk about things unrelated to General Motors. In other words, off-topic stuff. And anything else that does not fit Section Description.

Reply
 
 
 
Thread Tools Search this Thread
Old 01-29-2011, 06:00 PM   #1
Senior Member
True Car Nut
Thread Starter
 
Jonpro03's Avatar
 
Join Date: Jul 2010
Location: Danville, Illinois
Posts: 2,469
Thanks: 0
Thanked 0 Times in 0 Posts
Jonpro03 is on a distinguished road
Default Any electronics guys in here?

I know it'* a shot in the dark, but I need help with this. I'm the cheapest guy you'll ever meet. So spending money on a DC to DC power supply for my carputer is not an option for me. Why buy it when I can build it? So I've spent a couple of weeks in multisim building circuits, and I can't get anything reliable. Plus I have to account for the fact that voltages in a car can range form 10-14 volts or whatnot.


So my next thought was to just add 12V from the car to the point on the power supply after the rectifier. So I started researching power supplies. Then I found this:

http://reference.findtarget.com/sear...ower%20supply/

More specifically this:

Quote:
An SMPS designed for AC input can often be run from a DC supply (for this would be ), as the DC passes through the rectifier stage unchanged. It'* however advisable to consult the manual before trying this, though most supplies are quite capable of such operation even though nothing is mentioned in the documentation. However, this type of use may be harmful to the rectifier stage as it will only use half of diodes in the rectifier for the full load. This may result in overheating of these components, and cause them to fail prematurely.

Now, I've heard this before. Simply run the 12Vdc to the AC input of a regular PC powersupply. It sounded retarded to me when I heard it. Then I learned a little more about it and now I'm curious.

I understand why the diodes (I believe Zener) would burn up, and it'* no problem for me at all to replace those with some more appropriate ones.
Jonpro03 is offline   Reply With Quote
Old 01-29-2011, 06:30 PM   #2
Administratus Emeritus
Certified Car Nut
 
GXP Venom's Avatar
 
Join Date: Jan 2006
Location: Purgatory, Pennsylvania
Posts: 16,538
Thanked 7 Times in 4 Posts
GXP Venom is on a distinguished road
Default

IS this the same guy in almost in tears over his XBox with the wires soldered everywhere..... doesn't sound like this person is saving himself any money. Sorry, but BAHAHAHAhahahahahaha. It will work. It will create heat. That heat will compound as you go along, resistance builds heat builds more resistance builds more heat....... Just because something will work in itself. doesn't account for dealing with everything that goes on as it works. This is your XBox talking to you Jon, I hate you.......

Changing out the diodes is a step, but will circuits and paths take the heat. Kinda like punching out a block to accommodate a piston without figuring out if the wall thickness will still take the heat/compression. I believe those cheap Dollar Store phone chargers use this and they fry quickly, often taking a phone with it.
GXP Venom is offline   Reply With Quote
Old 01-29-2011, 06:33 PM   #3
Senior Member
True Car Nut
 
sawgunner's Avatar
 
Join Date: Jan 2009
Location: Dover, NH
Posts: 7,122
Thanks: 0
Thanked 0 Times in 0 Posts
sawgunner is on a distinguished road
Default

want a power inverter for you car i'll sell mine for cheap
sawgunner is offline   Reply With Quote
Old 01-29-2011, 06:44 PM   #4
Senior Member
True Car Nut
Thread Starter
 
Jonpro03's Avatar
 
Join Date: Jul 2010
Location: Danville, Illinois
Posts: 2,469
Thanks: 0
Thanked 0 Times in 0 Posts
Jonpro03 is on a distinguished road
Default

I have a DC to AC converter. I just don't want to use it because then I'm going from DC to AC back to DC and loosing a lot of power in the process.
Jonpro03 is offline   Reply With Quote
Old 01-29-2011, 06:46 PM   #5
Administratus Emeritus
Certified Car Nut
 
GXP Venom's Avatar
 
Join Date: Jan 2006
Location: Purgatory, Pennsylvania
Posts: 16,538
Thanked 7 Times in 4 Posts
GXP Venom is on a distinguished road
Default

Why use an inverter then. Why not a DC transformer?
GXP Venom is offline   Reply With Quote
Old 01-29-2011, 06:58 PM   #6
Senior Member
True Car Nut
Thread Starter
 
Jonpro03's Avatar
 
Join Date: Jul 2010
Location: Danville, Illinois
Posts: 2,469
Thanks: 0
Thanked 0 Times in 0 Posts
Jonpro03 is on a distinguished road
Default

That'* what I'm working on... but dropping voltages to 12V, 5V, and 3.3V when your input voltage is anywhere between 10-14V is not easy, that and I need at least 3 amps for each voltage. The thing is, I'm pretty sure that after going through the rectifier on a PC power supply, the output is 12V. So that'* where I want to apply voltage and say screw you to the rectifier side of the powersupply.
Jonpro03 is offline   Reply With Quote
Old 01-29-2011, 07:24 PM   #7
Administratus Emeritus
Certified Car Nut
 
GXP Venom's Avatar
 
Join Date: Jan 2006
Location: Purgatory, Pennsylvania
Posts: 16,538
Thanked 7 Times in 4 Posts
GXP Venom is on a distinguished road
Default

Saying screw you usually results in unwanted side effects. LOL . I haven;t been around hobby electronics in quite the while p\but it seems to me I remember dc transformers that allow you to tap into "legs" along the windings. This would be ideal for your project. Don't know the availability or cost.
GXP Venom is offline   Reply With Quote
Old 01-29-2011, 07:50 PM   #8
Senior Member
True Car Nut
Thread Starter
 
Jonpro03's Avatar
 
Join Date: Jul 2010
Location: Danville, Illinois
Posts: 2,469
Thanks: 0
Thanked 0 Times in 0 Posts
Jonpro03 is on a distinguished road
Default

So in order to get an ATX power supply to work on a DC input, you have to input ~220V. That'* not gonna work...


Back to working on applying DC voltage after the rectifier.
Jonpro03 is offline   Reply With Quote
Old 01-29-2011, 07:57 PM   #9
Senior Member
Posts like a Corvette
 
StealthGXP's Avatar
 
Join Date: Aug 2010
Posts: 1,337
Thanks: 0
Thanked 0 Times in 0 Posts
StealthGXP is on a distinguished road
Default

Your cheap ???

How much time have you put into this ??

I bet you could of picked up a nice inverter big enough to power what you need !!!

I mean I know that your learning .. But idk.
StealthGXP is offline   Reply With Quote
Old 01-29-2011, 08:03 PM   #10
Senior Member
True Car Nut
Thread Starter
 
Jonpro03's Avatar
 
Join Date: Jul 2010
Location: Danville, Illinois
Posts: 2,469
Thanks: 0
Thanked 0 Times in 0 Posts
Jonpro03 is on a distinguished road
Default

Well like I said, I have a 400W DC to AC inverter that I'm currently using. I just don't want to use it anymore. LOL
Jonpro03 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Any gamers in here? What are you guys playing? ComfyCar Lounge 43 07-09-2005 04:37 PM
electronics guys? L27Buick Lounge 1 11-08-2004 09:01 PM
Place to buy electronics Twister97 Lounge 1 06-13-2004 08:58 AM
Whats the diff between the SE and SSEi electronics. JrFaust 1992-1999 2 08-03-2003 08:46 PM
Forum for Electronics LowLyfe83 Forum updates and suggestions 4 07-06-2003 08:21 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 08:21 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.