I guess I have solved the powersupply question for my self and for all those people who do not have the source or money to invest in a redimade Power Supply.
How do i intend to solve the problem:
I will be using the inverter circuit of a UPS - 500VA or 600VA - the battery that comes in these UPS are rated at 12v 7.2mA - gives a battery backup of 15mins on a P4@3Ghz HT, 512MB RAM,250GB HDD,DVD-Writer,5.1 channel creative speakers, Creative LiveaSoundcard,Ati Radion x300 - 125MB Video card, 17" Sony TFT, and a ADSL Modem.
my car battery is rated at 650ah, as far as i remember...and after reading some documents and OReilly.Car.PC.Hacks.Jul.2005. I come to know that the ah rating is the time that the battery would last w/o any decrease in power and if a 7.2mA gives me 15 mins . 650mA should give me a lot...
i intend to use another battery with an isolator (please help me find how to make an efficient isolator) which would be powering my carputer when my car is off and the same battery would be providing me charge when i am running the car!! shcks..i am stuck here...now .. i would really appreciate if you guys could help me here
1. will the ups inverter circuit work ?
2. how do i get the isolator working?
3. how exactly should i power my carputer so that i can use the 2nd battery for runnin it when my car is off and use power generated by the altinator of the car when i am onroad....umm...
4. can i connect capacitors in series to make a large capacity capacitor so that my other electricals in the car do not go crazy when i am running the carputer...heard that the headlamps start dimming at bass..mine did some time back but with a new headunit and woofers they r fine now!!
dude, 650Ah what car do you drive ?
its more likely 65Ah
also your inverter would be using a 12v, 7.2Ah not a 7.2mAh battery
The 650 might be the CCA of the battery. A 650Ah battery would be enormous.
Old Systems retired due to new car
New system at design/prototype stage on BeagleBoard.
Search on terms "Tank Circuit". Better yet, click on the link in my signature to go to the FAQ Emporium. There's a thread in the FAQ to the FAQ's about power supplies. It explains tank circuits and provides a link to them.
How will you auto start and then shut down your PC?
A capacitor will not work for the application you are describing. Capacitors discharge very quickly and charge more slowly. They are designed to help for a split second, usually when massive subwoofers are being powered.
I'm not trying to discourage you about doing it yourself, after all, that's what this hobby is all about but by the time you buy the UPS, build the tank circuit, wire up a home made auto startup and shutdown circuit, you'll have spent your way quite a ways towards buying the power supply. Since the power supply also provides clean regulated power and you are depending on the UPS for that function, it seems as though the ready made product is worth the extra bucks.
Give it some thought.
With just the price of the second car battery, plus the little extra circuits and stuff your already over the price of the power supply.
I was hesitant when I bought mine becuase $100 for a power supply is a lot of money, but now that I have it I see it's really well made, and compact. Now that I have it I find it was worth every peny.
it is 12v, 7.2Ah i am sorry for the confusion..it definately is not a 650Ah battery I am running a small car..will check the Ah rating. it might be just 65Ah.
i cannot avail the PSU for the car pc , so everything that i want to do has to be made by me else i quit this project.
i have an old pc lying in my celler and i want to make use of it...I will upgrade it later as all i will have to do is change the
I appreciete you guys helping me please consider that everything has to be built by me and I know 0 about the PSU. I am a "computer guy" without hardware knowledge.I can just fix pc's too well and do it professionally! no jokes!
I have seen the inverter circuit for a 600VA ups today its about 12" x 4" . I will ask my friend to help me with the connections to that as he professionally repairs psu's.
the circuit i am taking about would cost me round about 600INR ie 13 USD approx.
I believe , i can use the com port for auto hibernate and the com port again for auto switch on...even if the auto on feature is missing i dont mind having a switch to turn the carputer turn on.
kindly help me with this project. i never knew about this forum until i actually thought about making a carputer and googled it up!
1. I Can actually use a UPS circuit
2. Use a relay - to keep the carputer on while i crank
2. I can use a tank circuit to have two batteries ...2nd battery to be used while cranking only
1. can use the 12v 7.5Ah battery as the 2nd battery?
2. what relay to use? Electricals is greek to me...kindly specify, if possible help me with the connectors...as to how to connect the relay....I will be using the tank circuit.
i dont want auto on feature! so i problem is solved
as far as puttin the pc to hibernate /shutdown i will use the com port to detect the power supply....i guess APC made such UPS's earlier...and I defiantely am sure if i dig into the forum someone already has the post to make a generic ups profile in windows and use the com port to auto hibernate
sincear appreation to all the members of the forum who are helping me persue this hobbie...kindly help if u know what i dont....
anyone ever turn an old APC into a plain inverter for a car?
I got a SU1000NET laying around with dead batteries and being it wont sell on ebay for $10, i might as well try to use it as an inverter, being they go for over $100 and i dont have one....
Your peak load will be the peak currents drawn by the pc, ups inverter (yes it will draw power) AND the 2nd battery when discharged.
Look at this site for more info on relays.