Thread: Diy 400w Psu

Hi to all
Some news:
I has wrote user's manual , you can download it here http://downloads.pilotpowersupply.co...wInstGuide.pdf (160Kb PDF )
If you'll find something wrong in this guide- please say it to me.
I tried to write this manual is very simply and clearly - with diagrams.

Also here is a simple site http://pilotpowersupply.com , (ti's under deweloping now) a little bit later I'll write some articles - how to build simplest startup/shutdown controller, which could be uses with inverter too, and about problems of ground loop, noises and interference schematics and wiring diagrams will be added - really DIY projects, not like this PSU - they more simplest.

Soon in this thread will be a special offer for beta-testers

I wouldn't mind beta testing a unit for you.

Maybe you could pm me a price for a beta unit?

My system runs fairly close to a 150w draw, and I have been considering a dsatx recently. My specs are available under my name on the left. It's a dell optiplex gx270 with an audigy 4 pci sound card and a dual head nvidia card. Your PSU should have little problem powering a system such as this. My board has a 20 pin connector, but I am unsure if it is ATX standard, I'll have to meter it. I also have a 4 gauge wire run to the rear of the vehicle from the battery for power.

I"m reading through your .pdf file right now. The psu seems very well thought out for features. One feature I would like to see incorporated would be an adjustable pot for startup delay of the external relay output wire. 2 seconds just doesn't seem like enough time for an amp startup, mine will "bump" when the sound card initiates and that somewhere around 10-18 seconds after start. I'm sure everyone else has different points (time) where the amps will bump/pop/sizzle also.
I also like the idea of your "ign never always" switch. Probably what I would term a "valet" switch. The only question I would have is there a capacitor in the system to cover the breif power drop as the switch moves from one position to the next or will the unit initiate shutdown when changing selection. IE: pull into the gas station, select "always", the voltage drops off (for a fraction of a second) during the switch movement and the controller initiates shutdown as it "sees" the voltage drop below 11v. Perhaps a better way to do it would be a "valet" style function. Have an adjustable pot to allow the user to sellect the "time out" before the unit shuts down, say, between 0-20 minutes or so. That way you wouldn't need the remote led to remind you you had left it on, the unit would automatically shut down for you.

I'd also be careful with the pricing, the DSATX is rated at 220w, offers the same features, is a proven unit, has a very small footprint (important to car users) and sells for $189 USD. This would be your major competion, I believe.

Although I'm not an electrical engineer, it looks good to me (so far).

Cheers

BJ

greatwhite
Hello.
I had saw your hardware description, as I know the dell motherdoards have a 20 pin power socket which is not compatible with an ATX standard - so I think it will be needs an adaptor..... but maby I'm wrong

One feature I would like to see incorporated would be an adjustable pot for startup delay of the external relay output wire. 2 seconds just doesn't seem like enough time for an amp startup, mine will "bump" when the sound card initiates and that somewhere around 10-18 seconds after start. I'm sure everyone else has different points (time) where the amps will bump/pop/sizzle also.

Ok, I will try to add this function - it's not difficult

I also like the idea of your "ign never always" switch. Probably what I would term a "valet" switch. The only question I would have is there a capacitor in the system to cover the breif power drop as the switch moves from one position to the next or will the unit initiate shutdown when changing selection. IE: pull into the gas station, select "always", the voltage drops off (for a fraction of a second) during the switch movement and the controller initiates shutdown as it "sees" the voltage drop below 11v. Perhaps a better way to do it would be a "valet" style function. Have an adjustable pot to allow the user to sellect the "time out" before the unit shuts down, say, between 0-20 minutes or so. That way you wouldn't need the remote led to remind you you had left it on, the unit would automatically shut down for you.

Switching is not a problem, when voltage drops , controller "sees" the voltage drop below 11v, then it waits about 15 seconds and check it again - if it stays dropped , controller shutdowns the system, else if it's ok - system stays to work-it's maded to prevent errors - as you know, when you crank engine voltage also drops below 11v, but you cranking it no more than 15 secs, thats why it don't intiates shutdowning of the system.

About vallet style function - I had think about it, but there is no place on PCB of PSU to install more powerfull controller, thats why it provides minimum of functions, but it's not a problem to use external controller.

I'd also be careful with the pricing, the DSATX is rated at 220w, offers the same features, is a proven unit, has a very small footprint (important to car users) and sells for $189 USD. This would be your major competion, I believe.
Although I'm not an electrical engineer, it looks good to me (so far).

As I know DSATX isn't a bad PSU. It's ltc3780 PWMs based, - so it's not isolated, and if some Fet die it could takes mobo and another hardware with itself too, am I wrong ? But it has more efficieny.
Small footprint -yes it's plus. But some peoples uses invertres - as you know it has sizes more than DSATX or uses powerstream's psus, without controllers as I know.
So mine PSU is isolated type, has a standard ATX PSU case( sizes a little bit less than invereter's). It survives engine cranking also. This psu is developed like alternative for peoples, who can't use DSATX and uses inverters - it more efficiensly solution than inverter+AC-DC psu.
About the price - it will be near 200$( little smaller or higher or 200 ) , but for beta testers 160-180$ .... it needs to be calculated.

Good luck

Ok I have added variable delay for relay output , like greatwhite described. It was a very good idea - thanks.

Originally Posted by MibMib

as you know, when you crank engine voltage also drops below 11v, but you cranking it no more than 15 secs, thats why it don't intiates shutdowning of the system.

some vehicles (european diesels) can in winter crank for longer than 11 seconds!

I dont know if that will be an issue, I doubt it, as once the vehicle has been started and ran for a few mninutes, it should crank and start in less than 11 seconds, only the first very cold start could be an issue.

Lez Yes , simplest logic of controller's work could be a bad joke in situation, that you have described , but I don't think that it's a big problem, user simply can install 3 position switch, then switch it to off position before first time of engine starting in the winter , and after engine's start switch it to "ignition" - this will be work perfect. Also this psu can work from 8-18 Volts source, and survives cranking.

Originally Posted by MibMib

ok - found some schematic, don't know author.
http://img81.imageshack.us/img81/5582/compcar2dw2.gif
200W
3.3 v,12v not stabilized , like in cheap psu - for not powerfull system is a good choice i think. But not pointed parameters of transformer but you can calculate this with some free special programs

p.s. oh - I found some mistake - C9 needs to change polarity

I would also recommend using a diode to protect the 5V_sb regulator from reverse polarity.

Originally Posted by MibMib

simply can install 3 position switch

Simple way often best

I like you project, I may have to get one...........

Miel Gibson

I would also recommend using a diode to protect the 5V_sb regulator from reverse polarity.

Very good Idea
lez


News:
1. Variable delay for relay output added and works good
2. Finally I have got a hi-resolution currentmeter from my local electronic parts distributor, and using it I found that in off- state it takes 25-28 uA - it's leakage current of capacitors and diodes
3. First beta testing unit is ready, I'll keep it within 5 days for man who first wrote me an e-mail, if he don't interesting in it - I'll give it to someone of you
The price of beta-testing unit is 180$.
There will be 3 units at the beginning of this month, and 5 beta-units at the beginning of july.
If there will be any problems or questions with this units(Must not be-when I am assembling them, I am checking all things),i'll try to help you remotely or you can send it back - I'll give you money back-full price of this unit( without money transferring and shipment taxes).

Before preorder and using them-read user's manual at http://downloads.pilotpowersupply.com , also there you can find an e-mail to contact with me.
If you still have any questions please describe them in this thread
Good Luck

P.S.
Also now I am developing simplest universal startup/shutdown controller which could be uses with inverter based , notebook or another supply based carpc- it will be an open project - sources and schemtic will be available - it's very simple project which you can build by yourself , kits also will be available. I am trying to build it very simplest- for peoples who don't have enough knowledge in electronics and programming.