Battery based tank circuit (tested) - Page 7

david_594 · 04-02-2004, 09:23 AM

It seems the simplest solution to the whole tank circuit idea would be hooking up the computer to a second battery. Then running the first and second battery in parallel with a relay placed in between on the positive line, the relay being closed when it is recieving power via the ignition line.

This benefits you by no voltage drop during cranking, the battery will always be charging when the car is running, and you can run the computer with the car off and no fear of killing the main battery

LESLIEx317537 · 04-02-2004, 09:32 AM

I say run the relay off the 12 volt PC power supply molex so the batt will only charge and be tied intot he circuit when the PC is on.
-This eliminates potential hazards of using a Ni-Cd in the car.
-It's been tested and works.
-8 Diodes is alot.

How many PC's you running? lol

My Setup survives cranks and I don't even have anything except for my stereo amp 1 farad cap. Woo hoo. I run everything off my PC PS, screen etc... and it's the 250watt Keypower.

Alessio · 04-02-2004, 09:34 AM

I use a radio shack DC to AC inverter and a 50 bucks UPS, never had a problem

david_594 · 04-02-2004, 09:37 AM

I was thinking more along the lines of an automotive battery, or mabey something off of a motorcycle.

Quote: Originally Posted by LESLIEx317537

I say run the relay off the 12 volt PC power supply molex so the batt will only charge and be tied intot he circuit when the PC is on.
-This eliminates potential hazards of using a Ni-Cd in the car.
-It's been tested and works.
-8 Diodes is alot.

How many PC's you running? lol

My Setup survives cranks and I don't even have anything except for my stereo amp 1 farad cap. Woo hoo. I run everything off my PC PS, screen etc... and it's the 250watt Keypower.

LESLIEx317537 · 04-02-2004, 09:45 AM

Yeah a SLA battery.

DC-AC inverters take up more space.

DC--->AC--->DC why?

Alessio · 04-02-2004, 12:00 PM

Quote: Originally Posted by LESLIEx317537

Yeah a SLA battery.

DC-AC inverters take up more space.

DC--->AC--->DC why?

One word : easy

I got a truck, so an UPS and an inverter under the seat is nothing

did I say easy?

zvi · 04-02-2004, 12:05 PM

Quote: Originally Posted by david_594

I was thinking more along the lines of an automotive battery, or mabey something off of a motorcycle.

I have motorcycle one, its 12v 9Ah, I'll post pictures of my battery tank setup on monday

Ricky327 · 04-02-2004, 12:10 PM

My Setup survives cranks and I don't even have anything except for my stereo amp 1 farad cap. Woo hoo. I run everything off my PC PS, screen etc... and it's the 250watt Keypower.

Isnt that because you are using a keypower PSU? I maybe wrong but isnt supposed to survive a crank anyway?

LESLIEx317537 · 04-02-2004, 12:26 PM

Quote: Originally Posted by Ricky327

My Setup survives cranks and I don't even have anything except for my stereo amp 1 farad cap. Woo hoo. I run everything off my PC PS, screen etc... and it's the 250watt Keypower.

Isnt that because you are using a keypower PSU? I maybe wrong but isnt supposed to survive a crank anyway?

no, only after i added the 1 farad cap.

Opus, can survive stock.

no1knows · 04-02-2004, 12:31 PM

i love barnsley

LESLIEx317537 · 04-02-2004, 12:36 PM

Usually DC - AC-DC will introduce line noise and other unwanted noises.

zvi · 04-03-2004, 12:42 AM

Quote: Originally Posted by zvi

I have motorcycle one, its 12v 9Ah, I'll post pictures of my battery tank setup on monday

here is my small Accu:
http://zvi.home.ge/pics/vextra/accu.jpg

LESLIEx317537 · 04-03-2004, 07:46 AM

zvi,

A 9Ah is way overkill, all you need is 1Ah if anything.

Also, assuming you have a Z, you probably take turns like I do, and I autocross. So a 9Ah battery placed in the car is just not ideal...

How do you have it wired up and mounted?

zvi · 04-03-2004, 11:00 AM

Quote: Originally Posted by LESLIEx317537

zvi,

A 9Ah is way overkill, all you need is 1Ah if anything.

Also, assuming you have a Z, you probably take turns like I do, and I autocross. So a 9Ah battery placed in the car is just not ideal...

How do you have it wired up and mounted?

Yes, I know, whole my system will use a bit of it, but this accu was easiest to find here (and cheapest), so let it be

Well I dont autocross, only if I am in hurry to somewhere

, it's just a peaceful, family car

I have wired it up as Ricky327 proposed in his first post, just only I have four of 1N5822 diodes (in place of one, total - 8) in paralel. I have 120watt PSU, so I assumed, that current coming from accu might be 10 amps, so I put four of 3 amp diodes, total can pass 12, besides: these diodes drop less voltage on less amps, so 4 of them drop less volts. Now, with no load, it drops 0.25v only
I have 12.35 with engine off, and 12.10v when cranking.
I have used 15 ohm Resistor, impedance I calculated also from Ricky's first post: 9ah Accu needs 0.9 amp for charging -> I have 14v with engine on-> as V=I*R -> R=14/0.9=15.5 ohm, so I found 15 ohm resistor.

The backup baterry just fits next to my main baterry

let me draw a circuit and pcb I have used...

zvi · 04-04-2004, 05:32 AM

the green colored is a copper on the back side of the PCB