Different colors have different current ratings.
I think those are 10mm Leds

 

Different colors have different current ratings.
I think those are 10mm Leds

They don't necessarily require different currents but they certainly have different forward voltages i.e. around 2V for green and orange or 4V for blue.

 

Whooops! I meant that?

 

1. 9V → 3V LED → 3V LED → R → 0V, I = 16 mA*50 sets = 800 mA
2. 9V*2 → 3V LED*5 → R → 0V, I = 16 mA*(100/5) sets = 320 mA

9V battery ENERGIZER 522, rating current Imax=600mA.

 

Because the different colours have different forward voltage (Vf) you can't simply wire them in parallel. The ones with the lowest Vf would hog most of the current and the others would barely light (if at all). Only LEDs having closely matched Vf should be wired in parallel.

 

Welcome to AAC.

What color is the light that you LEDs make?
This information will help us guess at the required voltage.

50 are green .. 20 orange and 30 blue ones

With this information, I've made the following assumptions:

Blue & Green: forward voltage of 3.6V.

Orange: forward voltage of 1.9V.

Assuming a standard current draw of about 20mA:

Blue & Green: 9V - (2 x 3.6) = 1.8V, then 1.8V/0.020A = 90 ohm current-limiting resistor. We'll say 100 ohm since blue and green will typically be very bright and 100 ohm is a common value.

Orange: 9V - (4 x 1.9V) = 1.4V, then 1.4V/0.020A = 70 ohm. We'll say 68 ohm since this is common and close enough.

You can put two blue or green LED's in series. This will help save current draw and reduce the number of resistors needed.

You can put four orange LED's in series, again for the same reasons.

We can't put more in series because then the voltage required for the LED's exceeds the battery's voltage.

Below is a quick wiring diagram for reference.

If I've estimated the values correctly, then we have 45 circuits needing about 20mA: 45 x 0.020A = 900mA, meaning the OP will need 900mA per hour (mAh). A good 9V battery will yield about 500-600mA total under a light load. For a heavy load (over 500mA), you'll get less than 400mAh. Let's say 250mAh as a working example. So, 250mAh/900mA = 0.2778 hours or about 16 minutes. And this is for a good quality battery. Cheaper batteries will run for even less time. Doubling the battery will double the life, so you could get about 30 minutes from two batteries.

The big question is, how long do you need the batteries to last between replacing them?

A lead acid battery would work - if you could get your hands on small UPS you could charge it using the power strip then take the battery out and run your LED's. These have a capacity anywhere from 3Ah to over 7Ah depending on the size of the battery. In other words, 3 to over 7 hours of run time per charge. Actually, it should last a little longer because we could then put more LED's in series (assuming a 12V battery) and reduce the total current draw.

 

Here's another way to do it that uses higher value resistors but provides more stable currents:

Connect the pp3 batteries in series to get 18V
Connect the blue LEDs in series groups of 3 with 1x 330Ω resistor per group (a total of 10 groups = 30 LEDs)
Connect the orange and green LEDs in series groups of 5 with 1x 430Ω resistor per group (a total of 14 groups = 70 LEDs)

Total current <500mA


But, PP3 batteries would not be my choice for this application.

 

I can use two 9v together no problem if these leds wont be damaged so I wont need any resistors?

You will need a resistor per series LED chain unless you use a constant current power supply.

Each LED has a fixed forward volt drop - if the voltage you apply is slightly under that it won't work, if the voltage is slightly over that the current will rise out of control and destroy the LED.

Some cheap flashlights rely on the internal resistance of the cells to limit the LED current - but the LED life expectancy isn't hugely more than a filament bulb.

 

I couldnt find small values resistors here :/ I guess im gonna wire every collor on its own battery of 9 v cant i just use one or two resistors instead of one for every dingle led

 

I couldnt find small values resistors here :/ I guess im gonna wire every collor on its own battery of 9 v cant i just use one or two resistors instead of one for every dingle led

Is there something wrong with you?

It is clear that anyone who continues to respond will be wasting their time.

 

I couldnt find small values resistors here :/ I guess im gonna wire every collor on its own battery of 9 v cant i just use one or two resistors instead of one for every dingle led

NO...
LEDs need some sort of current limiting.. A resistor does that..
You must have a resistor for each LED if wiring them in parallel or each string if wiring them in series.

 

Thanks everyone u have been such a great help ^^ I appreciate it