The far red thread

8

8/10

Well-Known Member
@Growlem can you link the datasheet for your leds?

What you need to know is this:

Led: The amps and voltage it needs (one affects the other so check the graph for accurate numbers)
driver: (constant current) amps and voltage it delivers

The amps (current) is the strength of the power and the voltage is how much it can deliver. So you can regulate the strength of the led by the amps and the voltage is how many leds you can run on a single driver.

If the leds can run on a current between 350-1000mA , you can then decide which driver to use. In this example 700mA is somewhere in the middle and should be good to go. Then you'll check how much voltage a single led draws at 700mA (looking at the graph in the datasheet). The lpc-35-700 delivers 9-48v, so if an led draws 5v @ 700mA you can fit 9 leds in that amount of volts (5v x 9 = 45v). (It is recommended to leave a couple of volts to spare).

So, in this example the values should be like this:

Led: 350-1000mA and check graph for voltage (ex. 5v @ 700mA)
driver: 700mA (constant strength) 9-48v (how much power)

at 700mA your leds need 5v each, so if the driver delivers maximum 48v it can supply power to 9 leds (5v x 9 = 45v which leaves 3 volts headroom). Forget about constant voltage drivers.
 
V

VegasWinner

Well-Known Member
Growlem said:
Looking into that.
Can you tell me what's the difference between these two models?
http://www.mouser.de/ProductDetail/Mean-Well/APC-35-700/
http://www.mouser.de/ProductDetail/Mean-Well/LPC-35-700/

Wouldn't it damage the IR-Diodes to drive them at 1050mA when it says 700mA in the specs?

Man, I didn't think I'd still have this much trouble figuring out the driver stuff, but for some reason I am completely lost right now when it comes to how many LEDs I can drive with, e.g. the Mean Well LDD-700H.
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according to Steves;eds they claim you can run up to 8 SemiLeds far red on one LDD-700, GM said in his video 10-12 SemiLeds. So i checked out a led selector and it said I could perhaps get up to fifteen on one string if their Voltage Forward is at or below 2.6v @700mA. I put a link you can go to and verify as well. peace.
 
8

8/10

Well-Known Member
It says on the link he posted earlier that the 3w leds draw 1.7-2.4v. If we stay on the safe side that means he could use the apc-35-700 and fit 50 / 2.4 = ~20 leds on one apc-35-700. The meanwell LDD-700H runs on 9-56vDC and won't be able to plug directly into your wall outlet.

buy an apc-35-700 and run 20 leds OR buy an lpc-35-700 and run 19 leds. presuming your planning on plugging the driver directly into your wall outlet.
 
testiclees

testiclees

Well-Known Member
@8/10

hey Bud could you shed any light on what's going on with my far red bar? I wired 6 x cree xpe 720-740 to my bar. (1000mA max, 2.25 forward voltage@.9mA).I wanted to test it out so i wired it to a modem power source. In the meantime my driver arrived but ive left my bar connected to the modem. I'm not sure of what's going on. For example this transformer doesnt even list DC output? Is there any advantage to switching it over to the APC. I tried to test with my meter and Kill a watt but it wasnt helpful.wtf driver.jpg

edit after some research: I could not determine exactly what effect running the string @10.5vac would have but I swapped out the power supply anyway. Still interested in what is going on when powering DC w AC at similar voltages.
 
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8

8/10

Well-Known Member
I don't know that much about it, but DC (direct current) means that the power goes in one direction through the circuit all the time, so the leds get their current in one end and out the other (+ -) but with AC (alternating current) the current alternates it's direction through the circuit and the leds in that circuit receive current left and right alternatingly, which doesn't work for them cause they're made to get current in one direction all the time. So if you run power in reverse through an led - wire to + on led and + wire to - on led it won't work or be damaged.

A driver is either DC out or AC out, for leds we want DC out.
 
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Airwalker16

Airwalker16

Well-Known Member
So it seems theres really no driver out there thats 1000 ma that isnt like the LDD where you need to use dc pigtails to insert a 12-36v "charger". I guess ill have to go with an lpc-35-700 to run 12 solderless xpe crees from rapidled because I really dont want to have to wire in and even buy the pigtails for the bucking drivers. (LDD). Im much more inclined to use the lpc-35-700 so I can plug it into an outlet on a timer and be done. But ive seen so many different numbers on how many they can actually run. I TRULY want to run my far reds at max 1000mas but its just not possible where the lpcs closest option is the 1050. But if I DO CHOOSE the lpc-35-700, how many far red cree xpe2s solderless from rapidled can I put on it? Id like to do 12. Seems like thats exactly what @Banana444 did on his build, except mine Will be 3 leds to 4- 36" U Channels.
 
P

PurpleBuz

Well-Known Member
Airwalker16 said:
So it seems theres really no driver out there thats 1000 ma that isnt like the LDD where you need to use dc pigtails to insert a 12-36v "charger". I guess ill have to go with an lpc-35-700 to run 12 solderless xpe crees from rapidled because I really dont want to have to wire in and even buy the pigtails for the bucking drivers. (LDD). Im much more inclined to use the lpc-35-700 so I can plug it into an outlet on a timer and be done. But ive seen so many different numbers on how many they can actually run. I TRULY want to run my far reds at max 1000mas but its just not possible where the lpcs closest option is the 1050. But if I DO CHOOSE the lpc-35-700, how many far red cree xpe2s solderless from rapidled can I put on it? Id like to do 12. Seems like thats exactly what @Banana444 did on his build, except mine Will be 3 leds to 4- 36" U Channels.
Click to expand...
700 ma is plenty for the far reds from rapidled. don't sweat it.
personally I use the apc-12, its cheap.
 
Hybridway

Hybridway

Well-Known Member
I have noticed with my HPS that just about all my bud except for the edges of the canopy (which has T-5's) goes through a second growth spurt, packing on tons of weight. New growth everywhere the HPS bulbs hit hard. I swear it's because of the IR. I'm wondering if my LEDs are going to produce this second growth wave, if they create enough rise in leaf temp. To make this happen, or if they produce enough IR? Pretty sure it's the bulbs. I sometimes put MH's (Hortrilux Blues) in the last week in 4 of the 10 hoods & I noticed they did produce the second spurt but not as much as the Hortri-Reds. Just an observation & theory.
 
Banana444

Banana444

Well-Known Member
Airwalker16 said:
So it seems theres really no driver out there thats 1000 ma that isnt like the LDD where you need to use dc pigtails to insert a 12-36v "charger". I guess ill have to go with an lpc-35-700 to run 12 solderless xpe crees from rapidled because I really dont want to have to wire in and even buy the pigtails for the bucking drivers. (LDD). Im much more inclined to use the lpc-35-700 so I can plug it into an outlet on a timer and be done. But ive seen so many different numbers on how many they can actually run. I TRULY want to run my far reds at max 1000mas but its just not possible where the lpcs closest option is the 1050. But if I DO CHOOSE the lpc-35-700, how many far red cree xpe2s solderless from rapidled can I put on it? Id like to do 12. Seems like thats exactly what @Banana444 did on his build, except mine Will be 3 leds to 4- 36" U Channels.
Click to expand...
I have a string of 14 xpes on the lpc-35-700
 
Banana444

Banana444

Well-Known Member
Hybridway said:
I have noticed with my HPS that just about all my bud except for the edges of the canopy (which has T-5's) goes through a second growth spurt, packing on tons of weight. New growth everywhere the HPS bulbs hit hard. I swear it's because of the IR. I'm wondering if my LEDs are going to produce this second growth wave, if they create enough rise in leaf temp. To make this happen, or if they produce enough IR? Pretty sure it's the bulbs. I sometimes put MH's (Hortrilux Blues) in the last week in 4 of the 10 hoods & I noticed they did produce the second spurt but not as much as the Hortri-Reds. Just an observation & theory.
Click to expand...
I should post some pics of my current run, i have 2 600w verticals going, hortilux eye, and the buds are seriously packing on weight, i easily will hit my goal of 1# per 600w. Then i have a 4x8 with 3 lights 4 cxb3590s each @~75w per cob. Buds are looking excellent in both areas but the hps seem to really add the bulk more so than the leds. Dont get me wrong i really like the leds, in a horizontal setup, they penetrate better than hps, especially with the angelina reflectors. I have been keeping temps 79-81 lights on, 66 lights off, so no coldness issues stunting the led side of things.
 
Isawthelight

Isawthelight

Well-Known Member
Airwalker16 said:
So it seems theres really no driver out there thats 1000 ma that isnt like the LDD where you need to use dc pigtails to insert a 12-36v "charger". I guess ill have to go with an lpc-35-700 to run 12 solderless xpe crees from rapidled because I really dont want to have to wire in and even buy the pigtails for the bucking drivers. (LDD). Im much more inclined to use the lpc-35-700 so I can plug it into an outlet on a timer and be done. But ive seen so many different numbers on how many they can actually run. I TRULY want to run my far reds at max 1000mas but its just not possible where the lpcs closest option is the 1050. But if I DO CHOOSE the lpc-35-700, how many far red cree xpe2s solderless from rapidled can I put on it? Id like to do 12. Seems like thats exactly what @Banana444 did on his build, except mine Will be 3 leds to 4- 36" U Channels.
Click to expand...
http://www.rapidled.com/mean-well-eln-60-48d-dimmable-driver/ 4 screws open up this driver. Adjust the SVR2 pot counter clockwise to set current to minimum. Wire up your LEDs with a current meter in series with driver outputs and LEDs. Power up and increase SVR2 until you get your desired amps. http://www.vinnymarini.com/pictures/rapid_docs/Using Your Dimmable Driver.pdf This dimmable driver can easily drive 10 to 16 of these http://www.rapidled.com/solderless-cree-xp-e-far-red-led/ The LPC-35-700 will drive 5 to 18 far reds at 700 ma.
 
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Airwalker16

Airwalker16

Well-Known Member
8/10 said:
Pretty basic diagram, and I don't know if this shows clearly what's going on or not.

Btw, a relay is a switch that can connect two wires when it is turned off (by the 12/12 timer in this case) so it' perfect to start a timer when the rest of the main power shuts down.
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@8/10 hey man I'm having a hard time figuring out this diagram. Over all the methods of timing frs yours seems the best to me. Could you please either pm me or post here a little bit of a "how to" for me? I really want to do what you've done because it turns them on at the perfect time and is just...well... Perfect! I don't understand connecting the wires together. My cxb light is all to one plug.
 
8

8/10

Well-Known Member
@Airwalker16 I'll try to write up a tutorial on how to do the fr relay timer tomorrow! It is kind of hard to wrap ones head around how everything is connected but it sounds like you got the main idea. Just ask if there's something in particular you're uncertain about.

I'll take some pics to show which wires go where.

Are your main lights controlled by a 12/12 timer?
 
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