Instructables

I'm gonna wire 90 IR LEDs

it'll powered with 9v Battery
I dont know how to do it
it has 9x10 trim
please help me
if the you can wire them corectly please show me
I really need it

a_1984 (author) 2 years ago
really?
I want it for photography @ night as an illuminator
i found a circuit for this
but i don't know it's wrong or right
help me
how can i use it for 2 or 3 hrs?
should i add more batteries?
how many?
could you design the best circuit?
i have to use rechargeable battery because the size is small and it's portable
please spot these items
thanks a lot
Did you get a circuit design from the site mpilchfamily posted? You notice at the bottom it says the circuit will draw 990mA. A standard 9V has a capacity of 500mAh: 500mAh / 990mA ~ .5 hours. If you get ultralife 9v you can get around 1200 mAh. Rechargable batteries can have even lower capacities, around 500-350mAh.
You can increase capacity by wiring batteries in parallel. This adds the capacity so two 550mAh batteries in parallel will deliver 1100 mAh.
To get 3 hours you could put 3 of the long life batteries in parallel.

We don't know if the circuit you found is wrong or right either unless we can see it. Link?

Why do you have to use rechargeable batteries? They are much heavier than normal batteries and they are the same size. If you plan on using this a lot then rechargeables might be worth it but you will need more to get three hours of use, probably around 8-10. At upwards of $5 each thats a lot of dough up front.
a_1984 (author)  bwrussell2 years ago
yes
you're right
what do you recommend ?
i can't use any non-portable electricity cause i'm out of reach and out of facilities
in your opinion,what should i do?
90 ir leds+what kind of electricity?
of course i haven't already had any experience of electronic projects
i want to use these light at least 3 hrs
could you help me?
could you guide me?
i'm lower than a beginner in this major (or branch)
if it would be possible send me in e-mail
a.amjadian@yahoo.com
Here is what I need to know first.
LED specifications. What is the voltage, probably around 1.3 v, and the current, around 100mA?

If you don't have any experience with a project like this go read THIS, it will explain things like series, and parallel and LEDS and resistors.

If you can get me the LED specs I can be more helpful.
a_1984 (author)  bwrussell2 years ago
imagine you would like to do this
90 simple IR LEDs
how to wiring
which resistors do you need?
i want a clear guidance and a circuit diagram
i can solder them :D (it's beyond me)
just a clear circuit diagram
thanks guys
you all are so efficient
Last chance before I flag this as spam.
What are the voltage and current requirements of the LEDs you have or are going to buy? To design a circuit i have to know that.
a_1984 (author)  bwrussell2 years ago
bah bah
thanks
i found a circuit with 15 resistors
but i he didn't say about measure of them
i gonna use it for at least 2 hrs,it doesn't matter how many rechargeable battery should i use
how long will it last is important
i have to use 9v(s) and i bought 90 ir LEDs for it
if u don't help me i'll find a way finally
thanks
Ok now that you have bought the LEDs can you tell me their voltage and current requirements? It should be on the package or the person/place you bought them from should be able to tell you.

Where did you get the LEDs from?

The reason he couldn't tell you the resistors value is you haven't shared the LEDs voltage and current requirements.

If you can tell me this I will be able to design a complete circuit for you with the correct number of batteries and resistor values.
a_1984 (author)  bwrussell2 years ago
thanks
but the salesperson or its package didn't have any infos about LEDs specifications
i've posted some photo of LEDs but seems it hasn't came
will it usful if i send you some photos of theme?
i'm so sorry cause i don't have any infos about that
send me your e-mail ,i'll send you all i have
i beg you do it for me
by the way, how can i my self detect the specifs of these LEDs ?
i mean,doing experiments by some devices
do not forget
sent your E-Mail Address
thanks a lot beforehand
excuse my goofs in ENGLISH language.i'm in INTERMEDIATE level :D
a_1984 (author)  a_19842 years ago
hey
i found it's specifications in a web site

it's said
Current = 30 mA
Voltage = 1.2v DC typical , 1.6v DC max

Was it enough?

now,could you draw and define the resistors correctly?
The image has your circuit with the value of the resistors. You will need 15, 68 Ohm resistors. I think 4 rechargeable 9V batteries in parallel will give you around 2 hours of good lighting. If you want more time just add more of the same 9V's in parallel.

If you want a more exact way to find out how much time you'll get or number of batteries you'll need this is how the calculation is done. Your circuit draws 450mA. Look at the capacity of your batteries, this will be in mAh, milliamp-hours. As an example lets say your battery says 250mAh. To find out how long this battery will last, 250mAh / 450 mA = .55 hours.
Batteries in parallel add capacities so two of those batteries in parallel = 250mAh + 250 mAh = 500 mAh. Now your time is 500 mAh / 450 mA = 1.1 hours.

You can work this calculation backwards to get the number of batteries you need. 3 hours * 450 mA = 1350 mAh needed for 3 hours of operation. 1350 mAh / 250 mAh per battery = 5.4 batteries. Round up to 6 batteries and you should be good for 3+ hours.
Remember to replace the 250mAh with whatever capacity your batteries are.

Does this make sense?
wiz-d.png
a_1984 (author)  bwrussell2 years ago
thanks a lot boy
well done

what kinds of rechargeable battery, in small size, over 9v do we have?
i mean,for these usages
rechargeable batteries come in all the standard sizes, but 9 Vs back the highest voltage punch for their size. You would need 8 AAA, AA, C, or D size batteries in series just to get 9 V.

9Vs are your best option. To reduce the size of the circuit you could just use two 9Vs in parallel and carry extra batteries to replace them when they ran out after an hour.
a_1984 (author)  bwrussell2 years ago
oh,OK
It's so kind of you
your answers were complete
thanks a lot
This site will give you what you need.
http://led.linear1.org/led.wiz
a_1984 (author)  mpilchfamily2 years ago
does it work correctly ?
it's an on-line software.does it calculate as well as an experienced person?
It does all the math for you. Unlike a person the software doesn't make errors in its math.
a_1984 (author)  mpilchfamily2 years ago
great!
i'm so appreciative
+1, you stole my go to "I'm going to wire XX LEDs" answer. :D

What are you going to use these for? A single 9 V will probably last for around 30 min.
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