Battery charge/voltmeter

[Craig]

OK, I was thinking about getting a voltmeter to check that my battery was all nice and charged and basically am wondering If I could wire up a set of LEDs instead, so that the more charge there is , the more would light, if this makes sense. Possible?

 

[Retepetsir]

Yes, but you'll need some electronics along with them.

Maplin do a simple one for 12V I think - about £10.

Otherwise just get a dial from somewhere like Ebay

You really need it to go up to 15V or so, as 14.4v is a common voltage when the engine is running.

 

[Craig]

Yeah I was trying not to use dials/digi displays,hence the LEDs idea, is it actually possible though Pete?

 

[Ed]

Craig thing is using an LED is not a great idea. Reason being that different times of day would make the led look brighter or not than it was etc..Even a very dim light at night looks bright. You really need a voltage meter of sorts if you want to know what is going on.

Ed

 

[Craig]

That is true, I was thinking something along the lines of using a potential divider and then wire the LEDs in series so that the more charge, the more number would light up, impossible?

 

[Andrew]

Yeah, it's a bargraph display

Simple kit here:
http://www.electronic-kits-and-projects.com/1034.htm

You want anything more complex, use a PIC.