Fanleaf's Huge 42 COB Array Build Plus Other Builds

Here is the updated list of the # of cobs you can use per driver. This should be correct now.

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jr21 said:
Here is the updated list of the # of cobs you can use per driver. This should be correct now.

Screen_Shot_2017-04-29_at_4_48_36_PM.png
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Not quite. When I get on laptop Ill explain.
 
Buckshot317 said:
Oh, from model # it was a 480 watt or 500 watt driver. And thought output voltage has a lot higher and get more chips off one driver, and it was a 1400 ma dimmable . Just wire it same way in series
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Youre right man. I thought for sure it was the 480w high amp low voltage one they have.

Prolly have fun finding that one in stock though
 
fanleaf said:
Guys, this is Ohms Law and cannot be argued. Ohms law is Ohms law. It's not my law. It's settled science.
Look guys. This driver has ONLY 143 volts to be used and stay within constant current mode. 143 volts divided by 4 cobs is 35.75 volts per chip that the driver can output and stay constant current. At 35.75 volts the 29SE chip runs at about 1.2 amps or 1200,mA. You cannot make the chip run at 1.4 amps or 1.5 amps or anything in between at 35.75 volts. That is simply ohms law. If this chip is provided 35.75 volts the maximum current it can use is 1.2 amps. This is not for debate it's Ohms law. 35.75X1.2=42.9 watts per chip or times 4 chips is 171.6 watts give or take a few watts for driver specs at the drivers peak constant current mode voltage!
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Hey Fan, where did you get the 1.2amps? I'm following along but I cant figure it out. If you only have 1 part of ohms law (v) how did you calculate (a) with out watts?
 
jr21 said:
Hey Fan, where did you get the 1.2amps? I'm following along but I cant figure it out. If you only have 1 part of ohms law (v) how did you calculate (a) with out watts?
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Ok the info is all there but let's simplify it....

First ABSOLUTE RULE OF ANY ELECTRONIC. AN ELECTRONIC WILL ONLY USE AS MUCH AMPERAGE/CURRENT AS IT NEEDS!!!

RULE OF ELECTRONICS NUMBER 2......VOLTAGE IS WHAT PUSHES CURRENT. (OHMS LAW)

Now, let's use this Cree chart for example.....

I
cree7.JPG
Looking at the blue line ok????
If you want to run this chip at 2000mA your driver MUST ABSOLUTELY MUST be able to feed it 36 volts. If your driver is capable of 3000ma but has a max voltage of 35 volts what do you think this chip on the blue line will run at??? The answer is ABOUT 1450MA!!! The only way to make it push more current is having a higher available voltage,,,,remember, voltage pushes current!

If you want to run this chip at 2600mA your driver MUST be able to do 2600mA with 37 volts available. If your driver only has 35 volts available the driver will only push 1450mA through the chip period.
 
jr21 said:
Hey Fan, where did you get the 1.2amps? I'm following along but I cant figure it out. If you only have 1 part of ohms law (v) how did you calculate (a) with out watts?
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So, to answer you further lets go back to the Vero 29SE..

If your driver can only provide 35.75 volts to a chip in constant current the current that that chip will use at 35.75 volts is 1200mA or 1.2 amps (per spec sheet). So ohms law says 35.75 X 1.2= 42.9 watts per chip.
 
fanleaf said:
Guys, this is Ohms Law and cannot be argued. Ohms law is Ohms law. It's not my law. It's settled science.
Look guys. This driver has ONLY 143 volts to be used and stay within constant current mode. 143 volts divided by 4 cobs is 35.75 volts per chip that the driver can output and stay constant current. At 35.75 volts the 29SE chip runs at about 1.2 amps or 1200,mA. You cannot make the chip run at 1.4 amps or 1.5 amps or anything in between at 35.75 volts. That is simply ohms law. If this chip is provided 35.75 volts the maximum current it can use is 1.2 amps. This is not for debate it's Ohms law. 35.75X1.2=42.9 watts per chip or times 4 chips is 171.6 watts give or take a few watts for driver specs at the drivers peak constant current mode voltage!

This is simply the wrong damn driver for 4 of the 29SE chips. Just because it lights up and looks pretty don't mean it's right. If you are seeing more than 175W from 4 of the 29SE chips you are nothing but lucky but at the same time your driver is no longer in Constant Current mode like it should be.
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You are correct fan that it is no longer in its constant current mode, when it senses an over voltage it goes into its static characteristics. Open voltage on the 1750 is 146v ÷ 4 = 36.5,it only takes 36.2 to achive the 1400ma on the 3500k chip, so the 50.4w is easily achievable on this driver. Now the driver will not go into over voltage mode and shut down until it senses 150v or more... This is were we get the little extra out of this driver. We are over 146v but do not hit the threash hold of 150v.. I have been running 2 of these drivers in parallel over 8 cobs for over 5 weeks now and have checked a few times to max it out and everytime it will go straight to about 436w then creeps up to 440-443w as the driver adjusts to the load given.. I just finished my second panel with same drivers, but this time i used 3x 3500k80cri and 1x 2700k90cri per driver and have got the same results. You are correct in your math fan, i am an electrician and know ohms law well, but these drivers have some play in them.. As do all quality led drivers.. After many led upgrades to fields, historical sites, schools, malls, i was curious to see if this would work as it has in my past experiences... And it does on my 4 drivers... I know im not getting much more than a 1400ma, but i was thinking of future cob upgrades to solid 36v chips.... Cxb2 if it ever comes out... Im not trying to argue or fight, just sharing my experience.
Cheers
 
You guys need to realize that a 36 volt chip does NOT mean its always 36volts. 36v will usually be at the center of it's current rating. You can run the Cree chip mentioned above from 100mA through 3600mA. The voltage you feed it determines the amperage it will eat. If you feed the chip 34 volts the current will only be about 1000mA. If you feed it 38.5 volts the chip can eat 3600mA for a total of 138 watts per chip.

The Vero 29SE is naturally at a higher voltage and coincidentally if fucks us on driver selection in a few instances where the Cree will still work fine.
 
jimmyclone said:
You are correct fan that it is no longer in its constant current mode, when it senses an over voltage it goes into its static characteristics. Open voltage on the 1750 is 146v ÷ 4 = 36.5,it only takes 36.2 to achive the 1400ma on the 3500k chip, so the 50.4w is easily achievable on this driver. Now the driver will not go into over voltage mode and shut down until it senses 150v or more... This is were we get the little extra out of this driver. We are over 146v but do not hit the threash hold of 150v.. I have been running 2 of these drivers in parallel over 8 cobs for over 5 weeks now and have checked a few times to max it out and everytime it will go straight to about 436w then creeps up to 440-443w as the driver adjusts to the load given.. I just finished my second panel with same drivers, but this time i used 3x 3500k80cri and 1x 2700k90cri per driver and have got the same results. You are correct in your math fan, i am an electrician and know ohms law well, but these drivers have some play in them.. As do all quality led drivers.. After many led upgrades to fields, historical sites, schools, malls, i was curious to see if this would work as it has in my past experiences... And it does on my 4 drivers... I know im not getting much more than a 1400ma, but i was thinking of future cob upgrades to solid 36v chips.... Cxb2 if it ever comes out... Im not trying to argue or fight, just sharing my experience.
Cheers
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You are still a bit confused bro. Just because you hook up enough chips that it needs more than 150 volts dont mean a driver will go into over voltage mode....Over voltage is a safety feature encase the driver malfunctions. You cant make it go into over voltage "mode" by hooking up more chips. It don't work that way.
Static voltage is the voltage that "sits on the output wires until it senses a connection".
The driver should never have to go into adjustment as it warms up period. Driver adjustments are instantaneously done to protect LED's.
Another thing. We are talking about a 240-1750 driver here. The driver runs out of voltage way too quickly and he would get more out of a 240-1400 with 4 chips than he does the 240-1750 as I stated plainly and simply because the 1400 model has more voltage available.
 
I give up trying to explain this. I just know I like to select the correct driver for my arrays. I don't like trying to run more from them than they can do in constant current mode. I'm sorry for those who are just now realizing they are running a driver that's out of spec for their array. I like my shit to match up and stay safe.
 
And if someone needs a driver or driver options for their array Im always glad to help.
 
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