what am i doing wrong with the power supply?

[t-maxxracer32]

http://video.google.com/videoplay?do...92818067&hl=en

hope this can tell you guys whats goin on!

thanks

[brijar]

Should be an easy fix. Make sure you connected the ORANGE wire to a RED wire. You didn't mention it in the video, so that would be the most logical explanation to me.
Make sure you did turn on the switch to the power supply.

Good luck,
Brijar!!!

[BrianG]

Well, I don't know about connecting an orange wire to a red wire (shorting 5v to 3.3v), but try hooking that resistor to an orange and black wire instead. Maybe the 5v line is not the one being used for regulation.

And, like brijar said, check the power switch in the back of the PS (if it has one) and also make sure the voltage selector switch (if it has one) is set to the right wall voltage.

Also, checking to see if the 12v has power by shorting it to ground is not the best method. Hopefully, any short circuit protection should kick in, but you could also blow something. The internal fan runs on 12v, so that is a good indicator to see if the 12v line has power.

[t-maxxracer32]

ya usually i use the fan but i just checked to make sure.. i wont do the spark method no more

and i connected the resistor tro the orange yellow and red plug but nothin! ill try the orange to red plug together and see if that helps... im having the same problem with 2 diff power supplys so idk what goin on!

[brijar]

According to this

OOPS!
I just checked, and it says that the PWR GOOD line is actually GREY on ATX power supplies! So you should actually connect the GREY wire to a RED one and the GREEN wire to a BLACK one.

IF you have an ATX power supply, please ignore the comment about the orange wire. It is just 3.3v, like BrianG said.

[t-maxxracer32]

lol well i went out and got another PS to see if the other 2 were duds (my dad has about 50 old comps... i didnt pay for any) and i figured out the problem!! WAHOOO!!!

when you connect the green wire to black i thought that the green wire you were supposed to use was the one that connected the metal part of the PS... i saw another random green wire coming up from the board and disconnected it and connected it to the black and WALAA!!

now i have 2 more that will work very easily!! anyone interested in buying a power supply? lol

[BrianG]

lol, that green wire that connects to the case is the ground wire from the wall. IIRC, my instructions thread specifically says to use the green wire from the motherboard connector.

Glad you got it sorted out!

[t-maxxracer32]

lol well i didnt think i had to read the instructions again but i guess it would have helped! lol

anyways i got it working and eveyrthing but it wont run for any longer than 15-20 min. i tried everything i culd think of (red to black on resistors orange to black... orange to red... tried using the red wires instead of yellow... tried using orange instead of yellow i got 2 more transistors to see if that would help... i took off all transitors..) nothing worked. im guessing the problem is that the PS only has 4 yellow wires... so it wont let enough current out or something idk. the red or orange wires (which has 6 of each) cannot power the charger so now idk what to do.

i hope that made sence.

thanks!

[BrianG]

If it runs, but cuts out after a certain amount of time, the thermal shutdown circuits of the PS must be kicking in. That usually means it is being pushed too hard. No matter how many resistors you use on the 5v or 3.3v line won't fix that; overloaded is overloaded.

The current PS you are using may just be too small on the 12v line to handle what you are trying to do. Look at the label on the side of the supply and read the +12v spec. Pick the supply with the highest current value.

If you are seriously having a hard time getting it to work, you can ship the best one to me and I can see what I can do to make it more stable. Don't know if the two-way shipping cost would be worth it to you, and there is no guarantee if I can do anything to make it better, but it's an option. Just PM me if that sounds like something you want to try. Seems a shame to go through several PS units and none work like they should...

BTW: Make sure you take that other green wire (the one that goes to the 120v AC ground plug) and connect it to the case somehow. That is to protect you from getting shocked should the case (being metal) somehow float at 120v. If that were to happen, a circuit breaker would blow, but that's better than electrocution.

[What's_nitro?]

Or if one isn't enough, you could modify a few more of the ~50 you have sitting around and run them in parallel.

[BrianG]

I don't know if I'd do that. For one thing, the combined PS units would make for a fairly large thing to tote around. For another, ANY difference in the actual voltage will cause the PS with the higher voltage to heat up for nothing. It would be far easier to find one that has the capability you need, or simply get an actual 12v PS made for this type of thing. Just my opinion of course...

[What's_nitro?]

Originally Posted by BrianG

I don't know if I'd do that. For one thing, the combined PS units would make for a fairly large thing to tote around. For another, ANY difference in the actual voltage will cause the PS with the higher voltage to heat up for nothing. It would be far easier to find one that has the capability you need, or simply get an actual 12v PS made for this type of thing. Just my opinion of course...

You could always use a higher-wattage resistor and run all of the regulation leads through it to help cope with any difference in voltage between the PS's. I'd also put a small bipolar capacitor between all of the (+) regulation leads to further smooth any V ripple. Maybe some bipolar caps on the output leads, too.

[t-maxxracer32]

well i wont take it anywhere but my house. it will sit in the same spot the whole time. is there anyway to bypass the thermaling?

my dad has a bunch of different types in the backyard so i will just check which has the highest
?currenT?

anyways thanks for your help brian and nitro!

o and if i cant figure it out brian i might send it to you (should only cost around 12-15 dollars there and back for priority)

[BrianG]

As far as the thermaling; it may or may not do that, there really isn't a way to tell without trying it. I still wouldn't do it though. The switching circuits are quite complex and who knows what kind of nastiness that could happen. It could work fine, it could overheat, or it could do "bad" things - who knows?

Like I said, I'm sure I can get it to be more stable, but no guarantees if I can do much else without really digging into the circuit. The output is limited by the choice of coils, transistors, and general design.

[t-maxxracer32]

ya i dont knwo anything about that stuff... maybe i will just check and see what i got to work with and go from there

thanks!