Ready made tank circuit?

**Alric** · 12-18-2003, 10:56 AM

http://www.brilliantstore.com/bs-2000b.htm

This should work as long as it passes current while simultaneously charging the device.

I'll buy it and give it a shot.

Any thoughts?

Cheers,

**shakes** · 12-18-2003, 11:10 AM

hmmm ....

the main problem i see is there's nothing stopping power to drain backwards into your car's system. I don't know if this will be a problem really.

Heck, for $40 it's worth a shot, and if it doesn't work those things are always handy to have anyway.

**Alric** · 12-18-2003, 11:18 AM

Heck, for $40 it's worth a shot, and if it doesn't work those things are always handy to have anyway.

Specially considering the kinds of things we are doing here!

Cheers,

**jol** · 12-18-2003, 11:25 AM

worth a shot for forty bux? naaaaaaah

**shakes** · 12-18-2003, 11:27 AM

considering these things are often $80 and you'll get $40 use out of it if you only use it to jump people ... yeah it's worth $40 for a shot

**NewTechFool** · 12-18-2003, 11:30 AM

It contains elements of a tank circuit. I have one of these in my trunk for jump starting my and other cars.
If you hook it up as is, you are just putting another battery in parallel with your main battery. You need a diode/relay to make it usefull.

Using the 12 volt charger and running your computer off the little battery is no good either, as the charging current is too low to drive the computer in the long term.

Also the battery that is in the device is not a deep cycle battery. It will probably die fairly quickly if used as such. It is a high amp shallow cycle battery.

**shakes** · 12-18-2003, 11:50 AM

that's what i was doubting ... you really need some diodes to control when this battery is used and when the car's system is used.

**mark_kendrick** · 12-18-2003, 05:09 PM

Originally Posted by shakes

that's what i was doubting ... you really need some diodes to control when this battery is used and when the car's system is used.

All you have to do is ground it to the car body then use the charging adapter on a switched hot source(charges while the car is on)

Then make sure you use the 12v+ off this battery to power the cpu.

instant isolated UPS

**Ricky327** · 12-18-2003, 11:45 PM

I had one and it broke after 1 month

**Jackso** · 12-19-2003, 12:12 AM

Originally Posted by mark_kendrick

All you have to do is ground it to the car body then use the charging adapter on a switched hot source(charges while the car is on)

Then make sure you use the 12v+ off this battery to power the cpu.

instant isolated UPS

Doing this would allow it to work like a tank circuit in that the computer would not die while starting the car. However, the computer wouldn't run long even with the car started as the charger that comes with such devices doesn't allow enough current to pass to run the computer. Most have the cigarette adapter with like a 3amp fuse MAX (since they use something short of cheap speaker wire as power wire). Also the short cycle battery will cause problems in the near future.