Need help to light up 8 LEDs with different color

Thread Starter

jenovauh

Joined Jul 4, 2013
246
Put D1-1 back in place & measure V at D1-1 with LEDs on & report finding
D1-1 is 9.53V

. Reset BBR1 to 10V and leave it there. Measure V at D1-2 & report finding.
D1-2 is 9.85V

Connect R22-2 to 10k pot & set wiper to D1-2 V minus .2V. Adjust R23-2 to where U4-1 switches , work potU4-1 will jump up & down; stop when just a little movement causes a switch back & forthReconnest R22-2.
Does it mean D1-2 is 9.85V - 0.2V? If so, I had adjusted the 10k pot and set wiper to 9.65V.

Remove U4-5 jumper. Except for unknowns should be ready for sunshine & shadows.
Okay jumper remove and I am testing it under the sun now.
 

tracecom

Joined Apr 16, 2010
3,944
Just start raining here and LED circuit went off and battery does not seem to be charged nor powering the LED circuit.
Is it possible that the battery has been depleted by all the testing and has not had a chance to be recharged? Maybe the solar panels don't have enough output to run the LEDs and charge the battery at the same time.

I know that you have answered this before, but please state again the objectives of the circuit. I have forgotten exactly what it is supposed to accomplish under all light/dark conditions. I need to try to put all Bernard's setup procedures together and try to understand exactly what the circuit is supposed to do under all light/dark conditions. Bernard certainly understands it, but I need to catch up.

It must be Sunday night there now and you will need to sleep soon. I have to go to breakfast and then to church, but this afternoon, I will try to do some testing.

It's getting there.
 

Thread Starter

jenovauh

Joined Jul 4, 2013
246
Hi Tracecom, my 12V SLA battery are fine. I have charger for that and always recharge them when they drop below 12V. Anyway the objective of the circuit are as below.

1: To light up 16 Red LEDs, 8 Orange LEDs & 4 Blue LEDs (If=20mA)
2: Using 2 Solar panel in parallel, each is 14V 300mA (Total 14V 600mA)
3: The circuit are able to pulse the LEDs at 720Hz or higher (http://screwdecaf.cx/sept.html) trying to do a circuit like this one without microprocessor.
4: Able to recharge 3-4 pieces of 3.7V lithium battery for backup when sunlight is not available. (Being using 12V battery now cause Bernard seem to forget about the 3.7V lithium battery.)
 

Thread Starter

jenovauh

Joined Jul 4, 2013
246
And you want the LEDs on when the sun is shining, and off at night and when it is cloudy. Correct?
Yes, basically want the LEDs to turn on until sun goes down or night. Cloudy and not at night should be powered by batteries. Actually I had asked before how to control that without photo resistor. Maybe the solar panel itself can do that job, I am not sure.
 

tracecom

Joined Apr 16, 2010
3,944
Yes, basically want the LEDs to turn on until sun goes down or night. Cloudy and not at night should be powered by batteries. Actually I had asked before how to control that without photo resistor. Maybe the solar panel itself can do that job, I am not sure.
That's different than what I thought. So the LEDs should be on all the time - powered by the solar panel whenever possible and powered by the batteries otherwise. Therefore, the only time the LEDs are off is when the solar power is not available and the batteries are too low. Correct?
 

Thread Starter

jenovauh

Joined Jul 4, 2013
246
That's different than what I thought. So the LEDs should be on all the time - powered by the solar panel whenever possible and powered by the batteries otherwise. Therefore, the only time the LEDs are off is when the solar power is not available and the batteries are too low. Correct?
The only one time LEDs are turn off is when night falls. Else it should be turn on all the time like how our sun works. The purpose of this light is mimize sunlight which plants that are grown indoor or the location that does not allow.
 

Bernard

Joined Aug 7, 2008
5,784
That is the way it is suposed to work. A quick overview:
It is dark but sun is comming up, SP V is increasing untill it is up to 4V where U2.1-1 switches from Hi to Lo, turning on Q3. If SP is not producing enough power to allow BBR1 to regulate its output at 10V, then B1 supplies power for LED's. If B1 V is below 11.5 V then Q3 it turned off, and B1 V must climb to about 12.5 V before Q3 can turn on again.
When there is enough SP power for BBR2 to supply a 14 V regulated V, it will charge B1, in doing so, it may load the SP enough to cause BBR1 to drop its output slightly below the trip point of U4.1, turning off Q4 which stops charge. May try disconnecting C6 to speed up turn off as we do not want D1-1 V to fall below 9.5 V which would allow B1 to supply LED's.
We just do not have enough SP operating data to more acuratley select set points.



































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tracecom

Joined Apr 16, 2010
3,944
Bernard,

What is the maximum operating voltage of the LEDs? Is it 9.3 VDC?

If so, then the maximum current through a red, red, orange string is 33mA, and the maximum current through a blue, blue string is 22mA. That would put the total maximum current at 308mA (without any PWM); is that correct and is it what you intended?

I have done a little research and it seems that Singapore is only 1 degree north of the equator, and the longest day of the year there is only about 8 minutes longer than the shortest day of the year. Thus, it seems reasonable to ignore that difference and just assume a 12 hour day year round.

I don't remember the output of jenovauh's solar panels. Can you refresh my recollection, and tell me what your assumptions were about the voltage out at various times during a clear day?

Thanks, and I am sorry about my forgetfulness.
 
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tracecom

Joined Apr 16, 2010
3,944
I got my boost-buck boards today and have constructed that portion of the circuit. Soon, I should be able to test the complete apparatus. I still have to figure out what to do about the battery.
 

Bernard

Joined Aug 7, 2008
5,784
tracecom, I have no clue as to a LED strings current, Once it was 17 mA with 150Ω changed to 120Ω, then red LED's changed so 3 in series measured 8.8V, a little to close to 9V, so 9V went to 10V. Not sure where 95Ω came from, was changed to a std. value of 100Ω. If 8.8V is still true, then with 10V supply difference is 1.2V / .02 = 60Ω, or 56 std.
I've counted on LED's drawing 200 mA, but it could be measured.
4 SP at 150 mA each are connected in parallel, OC = 14V.
 

Thread Starter

jenovauh

Joined Jul 4, 2013
246
I don't remember the output of jenovauh's solar panels. Can you refresh my recollection, and tell me what your assumptions were about the voltage out at various times during a clear day?
Hi tracecom, normally when under the sun on a clear day, the solar panel will put out around 16-17.5 open voltage and current will be around 580mA to 650mA.

1.How can I put a simple load to test the maximum output of the solar panel?
2.Assuming if one day, these set of solar panel is faulty. When I hook up a set of different solar panel. Does it mean that the circuit wouldn't work or everything have to readjust again?
3.is the circuit smart enough to use solar panel range for 12v to 18v rated solar panel?

I have other solar panels range from 6V 330mA(10 pcs) to 9V 240mA(6 pcs) which can be use.
 
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Thread Starter

jenovauh

Joined Jul 4, 2013
246
tracecom, I have no clue as to a LED strings current, Once it was 17 mA with 150Ω changed to 120Ω, then red LED's changed so 3 in series measured 8.8V, a little to close to 9V, so 9V went to 10V. Not sure where 95Ω came from, was changed to a std. value of 100Ω. If 8.8V is still true, then with 10V supply difference is 1.2V / .02 = 60Ω, or 56 std.
I've counted on LED's drawing 200 mA, but it could be measured.
4 SP at 150 mA each are connected in parallel, OC = 14V.
Hi Bernard just to refresh your memory, the resistor for the LEDs in series was changed a few time cause when you initially design the circuit and did not cater for the pulse frequency above 720hz 25% duty cycle. Which I had later reminded you a few time then we start changing it to that requirement.

Just a question of doubt, when the 555 timer pulsing above 720hz 25% duty cycle, can each LEDs still draw 20mA current? Reason I ask this question is because when I last measured the current draw from any string of LEDs. It is only drawing about 10mA on Red strings and 13mA on Blue string. Tonight when I am back home, I will confirm their current draw with the current design of the LEDs circuit and update again.
 

Bernard

Joined Aug 7, 2008
5,784
Just a quick note for jenovauh, when measuring LED current; be sure that LED's are static, not flashing. You can ground Q1-3 & measure V across some of the 100 Ω Rs, R5 -R9, with VCC [ 555-8 ] of 10V.
 
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