diy led help

[rodster912000]

just finished wiring everything up and last step is to hook up a DDC-01 PWM Controller from rapid led. once i did that thing worked great except for the fact that when the leds are dimmed down low they blink on and off. anyone know whats going on here and maybe how to fix this??

 

[NirvanaFan]

how many mA are you pushing through them, and what type of LED?

 

[jfl14609]

if you are using meanwell drivers they cant dim below 10%

 

[rodster912000]

the leds are 8 cool whites set at 1450ma and 8 royal blues set at 950ma. everything was bought from rapidled. i know that the meanwels shut off when below 10% but these are flashing on/off. when i check the volts coming out of the pwm there in the negative when this flashing is occuring. but when they are brighter arround 40% power there volts correspond with the percentage. but when it drops below that the values go negative and the leds flash.

 

[jfl14609]

what meanwell are you using

 

[rodster912000]

60-48p

 

[jfl14609]

I am sure Nate will chime in he knows for sure but I am thinking somewhere I read a spec that you need to run a maximum of 14 with that unless they are in parrallel

 

[rodster912000]

ok so i figured that problem out. i didnt have enough leds on each driver....added one white and one rb to each and no more blinking. i guess it is some sort of sfty feature on the meanwells. no i am having trouble prgraming this pwm. there is three light setings with ramp ups of 30 min, 45min, or 1 hour. when i pick one it only seems to ramp for about 4 minutes then snaps to full power.

 

[jfl14609]

Go figure I wrote about there needing to be 9 bulbs min then I went back and edited to change to the max when I thought you only had one driver

 

[eamike261]

With 8 CW at 1450mA and 8 RB at 950mA, aren't you getting horrible color? When I turn my blues to 900mA I like my CW to be just below 900.

 

[der_wille_zur_macht]

Looks like you guys figured this out already, but yeah, this is a clear sign that the driver isn't loaded correctly, i.e. the total Vf of the LEDs is outside the operating range spec'd in the driver's datasheet. (being above the driver's max drive current probably isn't helping).

eamike, it really depends on the models and bins of LEDs involved - it's hard to make generic statements.

 

[rodster912000]

thos MA i set the drive at are the maximum, i can dim them down with the pwm to my liking. but still having trouble with the pwm, it dosnt seem to work how it is descibed to work. the instructions tell me specific ramp times and total daylight time for three setting but no matter what one i choose the leds glow very dim for about 4 minutes maybe less and then jump to full power. i understand the meanwells and the 10% power thing as i have a led array i diyed running on a reefkeeper that ramps up and down perfectly. but trying to help somone else diy this light with the pwm is proving to be very difficult!!

der wille have you got any insight on this issue?

 

[rodster912000]

im ready to scrap the drivers and pwm and order driver for a reefkeeper, then buy a rk and alc and do it that way...

 

[der_wille_zur_macht]

I'm not familiar with that particular controller in any intimate sense so I can't really comment on how it functions. If you can't get any help from the vendor who sold it, I would suggest checking the signal from it - in an effort to isolate the problem to either the driver or the controller.

 

[rodster912000]

i think i may have figured this thing out....what a pain to program.