PWM / LED Flicker

Related to the development libraries, released by Curt Binder
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saf1
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PWM / LED Flicker

Post by saf1 »

HI - quick question (I hope).

I am using Steve's LED retro kit over a Oceanic 29 Gallon BioCube and noticed it is flickering. Not sure if I am explaining it right, sorry; but that is the best way to describe it anyway :) I am using the PWM signal to adjust it starting at 1% for white/blue and going up throughout the day up to 90% then back down. It works great with the default library / routine that does it.

His drivers are pretty fast and I'm wondering if there is noise or a way to smooth it out somehow? The flicker is really starting to annoy me and I don't recall if this happened from the get go or not. I've double checked with the voltage on the power supply like his docs suggested. I shot him a email and he didn't say anything really indicating it was a problem. Just not sure what my options are, if any.

Tomorrow I'm going to manually override the PWM slope and see if I can just set them to 80/90% and see if it still flickers. I think I tried this already and it still managed a flicker but will double check.

The signal is set and correct, and it works. I just see throughout the day a flicker when it adjusts or if a relay flips on to one of the power heads it seems.
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cosmith71
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Re: PWM / LED Flicker

Post by cosmith71 »

You may have some noise coming back from the power heads when they shut off. Make sure they're plugged into ports 5 and 6, as those have some feedback filtering built into them.

Other than that, I don't know much about Steve's LED's. :(

--Colin
Sebyte

Re: PWM / LED Flicker

Post by Sebyte »

It sounds like you are getting a drop in voltage or a spike. Are you using ports 5 & 6 for your wave makers? They both have slugging in the contacts to cut out spikes and protect the contacts from arcing with rapid making and breaking. If other ports are being used you could get a spike as the contacts open, and cause the LEDs to flicker.
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lnevo
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Re: PWM / LED Flicker

Post by lnevo »

Are your drivers plugged into the relay bar? Try plugging them to a separate source. Steve's drivers should power off when dimmed to 0.
saf1
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Re: PWM / LED Flicker

Post by saf1 »

Thank you all for the several replies and what to look for.

The powerhead isn't plugged into port 5 or 6. In fact, I belive it is in port 2 or 3. I assumed, and incorrectly, that each port was the same on the relay box. Sorry about that.

Lnevo - not sure I understand the relay bar. Sorry. They do power off when set to 0 if I recall. I'll have to pull up my source and make sure. I use the default sketch built by the software provided here so I'm pretty new with it all. I believe I have the port the power supply is plugged in for the LED's turn on at 8 with the starting PWM either 0 or 1. I'll have to check. The power supply is also in the relay box. Sounds like I should move that to its own source? Let the RA go from 0 to whatever percentage, then back down, and lose power that way? I thought I had to enable it on, then dim.
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lnevo
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Re: PWM / LED Flicker

Post by lnevo »

Yes, you should remove the powersupply for the drivers from the relay bar. It's a waste of a controlllable port. You do not need to turn it on and off as the dimming to 0 should power off the drivers.

That would eliminate any noise from switching the powerheads and other sources. You shoudl also move the powerheads as you note above to 5 and 6. It's better for them long term...
saf1
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Re: PWM / LED Flicker

Post by saf1 »

Hi All.

Quick update. I went ahead and made the recommended changes has everyone noted. I fired up the arduino reef angel sketch tool, then opened the wizard. I have a pretty basic tank as I noted above but here is what I did.

1. Moved LED power supply off the relay box to a surge protector.
2. Moved return pump to plug 5 (not sure if that is necessary since it is always on unless I hit feed button)
3. Moved Koralia Evolution 240 to plug 6 (docs made it sound like it can be switched on/off)
4. Random port 6 (60 - 100)
5. Adjusted pwm for day light and actinic starting at 0, ending at 90 and 80 respectfully

I think that is it. I really don't have anything else power wise on the tank. I will be adding a second koralia so may have to swap out the return pump? I also need to recalibrate my PH probe since I don't recall writing down the numbers so I can add the values to the sketch. I'll do that next time.

Only issue I see so far is that Arduino 1.0.1 updated the libraries to 1.0.9 and I have the memory issue from the RA Client. I seem to run into this often and I remember it needs a new update too. I'll seach the boards and try and find it.

So far, no flicker. I should have asked this months ago but I thought it was the power supply itself going out. Thank you all for your time and help.

-scottf

*****6/29/2013 8:17:00 AM*****
Message:
Value cannot be null.
Parameter name: String
StackTrace:
at System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal)
at System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info)
at ReefAngelClient.Form1.DisplayMemoryValues()
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cosmith71
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Re: PWM / LED Flicker

Post by cosmith71 »

Aren't the pH values stored in memory when you calibrate? Wouldn't think you'd have to hard code them.

5 and 6 are the protected ports. If you get another powerhead I'd definitely move the return pump and put the Koralia on there instead.

--Colin
rimai
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Re: PWM / LED Flicker

Post by rimai »

Roberto.
saf1
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Re: PWM / LED Flicker

Post by saf1 »

Not sure how that works Cosmith. I know my sketch doesn't have anything with the numbers I used when I calibrated it. Also not sure what happens to the memory when you upload a new sketch like I did today. I just assumed that it would clear everything and I'd have to do it again.

Side note - THANK YOU ALL. The flicker is gone. Moving the power supply off the relay box and using port 5 and 6 did wonders. Not one flicker at all today and I'm really happy.

Also - the topic you posted Rimai - I actually have the file it mentions to download but doesn't appear to be working with the 1.0.9 build libs. I'll try again here in a few and see if it works. I've stopped the service, loaded the file, closed the client, restarted service and client, same issue.
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cosmith71
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Re: PWM / LED Flicker

Post by cosmith71 »

Memory doesn't reset when you upload a new sketch unless you upload a new memory file along with it. You should be good there.

Glad your problem is fixed!

--Colin
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