Meanwell LDD driver: for those who want to dim to 0 using Arduino
- Thread starter pwreef
- Start date
jjoos99
New member
I just bought a used arduino based light with about 140 leds and 3 ldd-h breakhout boards. It is a total mess and I dont know where to even start to figure out how all this goes together. I have read through the first 10 pages of this thread and have found nothing. Is there a build or information on how the arduino is wired and controls the breakout boards? there are wires broken off the arduino and wires that jump between the breakout boards.:headwally: Thanks in advance for any direction you can send me.
Jeff
Jeff
theatrus
100-mile-commuter
jjoos99
New member
Here is a couple pics of what I have. Everything is soldered connectors on both the meanwell breakouts and the arduino. How many different ldd's can be controlled from the arduino? where can I find out how to wire it all up. I believe it is using cap 5 wiring. My current setup is using 12 individual non dimmable drivers with strands of 12 leds. I would love to combine both systems together if possible. How do you determine which ldd to use (600, 700, 1000)?
thanks for any help
Jeff
thanks for any help
Jeff
oreo57
Well-known member
You can dim anywhere from 18 to 377 LDDs collectively, depending whose math you use..
As to figuring out an LDD for a 12 LED serial string, you need to know the diodes specs..
Generally 350mA for "normal" 1W diodes, 1000mA (750 being better) for 3W diodes.
covers most blues and whites..
That soldering job on the Aduino should be cleaned up (removed) and done as a plug or something more elegant, for starters..Really looks to easy to get bridging..
If it looks like something I'd do.. it is wrong.. and it looks like something I'd do..
As to figuring out an LDD for a 12 LED serial string, you need to know the diodes specs..
Generally 350mA for "normal" 1W diodes, 1000mA (750 being better) for 3W diodes.
covers most blues and whites..
That soldering job on the Aduino should be cleaned up (removed) and done as a plug or something more elegant, for starters..Really looks to easy to get bridging..
If it looks like something I'd do.. it is wrong.. and it looks like something I'd do..
:lmao:If it looks like something I'd do.. it is wrong.. and it looks like something I'd do..
Like it.
For the cost, I'd be tempted to get new boards. Either buy them or get some made (O2Surplus has posted some Gerber's in this thread, as has JoshLawless!).
Tim
jjoos99
New member
Can someone recommend which drivers I should be using? I will have 3 strings of twelve 3w cree whites, 6 strings of twelve 3 watt cree royal blues and 3 strings of twelve 3w cree mix of royal blue and violet. I will be adding five 3 watt red and six 3watt green. The used drivers that I have are eight 1000mah, one 700mah two 600mah and one 350.
thanks
Jeff
thanks
Jeff
oreo57
Well-known member
What, and how big is your power supply?
That has a little to do w/ what you want to do.
also picking drivers w/out knowing the electrical characteristics of the diodes is not "good practice"..
That said you do have some "common" and flexible guesstimates..
except for the violets most "3W" Led's can be run at any of the above drivers output. Only difference will be brightness and heat..
BUT.. certainly no guarantee..
That has a little to do w/ what you want to do.
also picking drivers w/out knowing the electrical characteristics of the diodes is not "good practice"..
That said you do have some "common" and flexible guesstimates..
except for the violets most "3W" Led's can be run at any of the above drivers output. Only difference will be brightness and heat..
BUT.. certainly no guarantee..
oreo57
Well-known member
W/out knowing the diodes "desired" range.. this is all a guesstimate.. But most 3w violets max out around 700mA.. Use the 600, 350 will prolong their life (or be the correct one..
)BTW: Not guaranteeing any of this.
IF any of these are 1W LED's then all bets are off..
48-3 = 45V available to the strings (counting for LDD needed differential).
Assuming max V(f) is 3.6....12 diodes..
Reds run below 3V in the range of 2.x...but unimportant w/ constant current really..
jjoos99
New member
If I want to run my strings at the 750mA level you suggested with the 1000 ldd can I just reduce the output with the arduino controller? with the controller set at 100% which is 255 on the controller if I would set the controller to about 190 it would be at the desired level of 750 mA if I am thinking right?You can dim anywhere from 18 to 377 LDDs collectively, depending whose math you use..
As to figuring out an LDD for a 12 LED serial string, you need to know the diodes specs..
Generally 350mA for "normal" 1W diodes, 1000mA (750 being better) for 3W diodes.
covers most blues and whites..
That soldering job on the Aduino should be cleaned up (removed) and done as a plug or something more elegant, for starters..Really looks to easy to get bridging..
If it looks like something I'd do.. it is wrong.. and it looks like something I'd do..
thanks
Jeff
No. The LDDs simply switch on and off really fast at their rated output. So if you run an LDD1000 at 75% what you get is 1A for 75% of the time and off for the other 25%. That is the difference between PWM dimming and analogue dimming.
Tim
jjoos99
New member
I just checked and it is that size. It is a good 6in wide by a foot long and has 2 cooling fans on it.
Jeff
jjoos99
New member
So will I be damaging my leds by driving them off the ldd1000's? They are the cree 3 watt royal blues and whites. I hate to have to replace all 11 of the 1000watt ldd but dont want to fry out my led strings.
thanks
jeff
The LDD1000 are not 1000 watts. They are 1000m/amp , I think you are getting your watts and amps confused. The thing to calculate is volts and amps. You need to calculate how much volts is going to used by the Lee's in a string. The amps will be whatever the driver is putting out. You new to check the fvolt and maximum amp of your LED. Wattage is only heat.
