Battery level indicator - Tri-colour?

[Jason S]

Hi,

I want to use a tri-colour LED (or maybe just 3 different coloured LED's) to
monitor the output voltage of a circuit, to tell me if the voltage is normal
(green), too low (amber), or too high (red).
I have seen the "Bi-colour LED battery voltage indicator", but was wondering
if there is such thing as a 3-stage indicator rather than just a 2-stage.



I would like some links or schematics to assist me. I haven't had much luck
using search engines.



Thanks in advance.

 

[Kevin Martin]

Hi,

I want to use a tri-colour LED (or maybe just 3 different coloured LED's) to
monitor the output voltage of a circuit, to tell me if the voltage is normal
(green), too low (amber), or too high (red).
I have seen the "Bi-colour LED battery voltage indicator", but was wondering
if there is such thing as a 3-stage indicator rather than just a 2-stage.



I would like some links or schematics to assist me. I haven't had much luck
using search engines.



Thanks in advance.

You mean like this one from Jaycar

<http://www1.jaycar.com.au/productVi...2=K&pageNumber=&priceMin=&priceMax=&SUBCATID=>

Kevin Martin

 

[Mikegw]

Hi,

I want to use a tri-colour LED (or maybe just 3 different coloured LED's) to
monitor the output voltage of a circuit, to tell me if the voltage is normal
(green), too low (amber), or too high (red).
I have seen the "Bi-colour LED battery voltage indicator", but was wondering
if there is such thing as a 3-stage indicator rather than just a 2-stage.



I would like some links or schematics to assist me. I haven't had much luck
using search engines.



Thanks in advance.

For three colours you only need two leds, consider what happens when both
are on.

Search for "window detectors".

How about something like this. I will set something up for a car battery.
To make up some numbers say one detector(A) turns on below 12 V. The
other(B) turns off below 10V.
Now with a bicoloured led hook A to the red led, B to the Green.

Batt V DetectA Detect B Colours
9 ON OFF RED
11 ON ON RED + GREEN= AMBER?
13 OFF ON GREEN

I know that the problem with this system is that Green now becomes the
colour for overvolt, but it gives you a start.

HTH

Mike

 

[Jason S]

You mean like this one from Jaycar

<http://www1.jaycar.com.au/productVi...2=K&pageNumber=&priceMin=&priceMax=&SUBCATID=>

Kevin Martin

hmmm, no, I'd rather not have 10 LED's. A tri-colour would be nice, or just
a green, yellow and red LED. I'm sure it's possible. But thanks anyway. =)

 

[Jason S]

For three colours you only need two leds, consider what happens when both
are on.

Search for "window detectors".

How about something like this. I will set something up for a car battery.
To make up some numbers say one detector(A) turns on below 12 V. The
other(B) turns off below 10V.
Now with a bicoloured led hook A to the red led, B to the Green.

Batt V DetectA Detect B Colours
9 ON OFF RED
11 ON ON RED + GREEN= AMBER?
13 OFF ON GREEN

I know that the problem with this system is that Green now becomes the
colour for overvolt, but it gives you a start.

HTH

Mike

Umm ok, that sounds like a start I suppose. I'll check it out later on.
Thanks =)

 

[dmm]

Hi,

I want to use a tri-colour LED (or maybe just 3 different coloured LED's) to
monitor the output voltage of a circuit, to tell me if the voltage is normal
(green), too low (amber), or too high (red).
I have seen the "Bi-colour LED battery voltage indicator", but was wondering
if there is such thing as a 3-stage indicator rather than just a 2-stage.



I would like some links or schematics to assist me. I haven't had much luck
using search engines.



Thanks in advance.

Jaycar have an RGB led for $5.95 (ZD-0270).
You could also use a bi-colour led. Use the green and red for the normal and
high functions, then oscillate the signal to the led to create amber for the low
indicator.

 

[Jason S]

Jaycar have an RGB led for $5.95 (ZD-0270).
You could also use a bi-colour led. Use the green and red for the normal
and
high functions, then oscillate the signal to the led to create amber for
the low
indicator.

Thanks. I'll take that into consideration, as I've read that a 3-pin package
is not as common as the 2-pin. Easier to install on a PCB also. Now all i
need is a good battery level circuit that will control it for me! I'm
looking for a schematic as I want to be able to twink with the
components/operation. Like I want to be able to control the low, normal and
high voltages with precision, if possible. e.g. 13.6V.