Ok is this what I need to run at 100w a piece.
Yep. Did you shop around for those any? You can save $30 alone on the drivers from arrow.
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I searched and searched for the cob’s and found a few but arrow was the cheapest.
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What’s a 100w on those COBs? Around 90%?
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You mean compared to max rating?
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Yeah aren’t they rated at like 118 or something? I guess I could quit being mentally lazy and go look myself. Heh.
Veros are more efficient at higher wattages, right?
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3420ma is max on c version, so 1400ma isn’t even 50% of max.
They hang in pretty tough higher indeed. Those charts u had from riu may be a little too old the have the b and c versions of the vero’s. But someone may have posted something newer on that thread. I’m not exactly in the right place though spend my Sunday scrolling through it looking though lol.
I’m pretty sure this is what the Plc 6 uses, c versions at 1400ma anyway. Since there are 6 cobs in that it. Probably used two hlg-320’s for drivers. Third party testing has it at 1.91 umol/joule. If I read and remember correctly, your citi’s at 1050ma were around 2.2 umol/joule. Watt for watt, you’re something like 10% more par efficient. For what it’s worth, you’re not pushing your heatsinks to edge of their ability either.
Running something like 29’s, big citi’s, or luminous hard is the cheapest way to get Watts in your tent from led standpoint. It’s not the best way to take advantage of led efficiency. When you look at what you’re getting for still in the neighborhood of $1 per watt, you can buy a gavita hang it and be done. It’s 10% difference from that to plc-6, 10% difference from plc-6 to what you have. So how much are you willing to do or spend for 20% more light? Want another 10%? Get into the bigger models or cxb and run them at 50 watts. Another 10% can be had running them at about 30 watts. Cost per watt to build that is getting pretty steep though.
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What would be a good spacing of the cob’s when ran at 100w? Stay at 16” or move to a greater spread? What kind of distances should I keep the lights from the canopy during the different growing stages?
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I’ve never ran 100 watt cobs. The timber fixture looks to be about 16 or 17” on centers, and they’re claiming over ppdd is over 1000 at 18”, they’re also using reflectors. I’d guess 18” on center and flowering down to 18” height would be ok. You’d want to be higher during veg though, and then gradually harden your plants.
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Would I be better off running at 75w? I was under the impression that the vero at 100w was a good combo.
It’s more like the vero is one of the best at 100 watts. It’s subjective right. They would be more efficient at 75 watts, but you’re not going to have as much light in your tent.
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The last thing I ordered got here the quickest so I now have 4 3500k cob’s and 2 c1400b drivers. I forgot to switch from the B to the A driver so now I need to get a dimmer. Would be nice to dim both with one dimmer but I’ll settle for 2 dimmers. What would be the best option here @dbrn32.
Heatsinks will be delivered tomorrow and the rest on Thursday.
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You can dim both with a single dimmer. I think you need a single 50k ohm potentiometer and 5k ohm resistor. Been a while since I looked at doing two though. So maybe do some google searching and see what you can find before ordering. I may have some time to look later, but a lot going on today.
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Ordered 50k potentiometers and 5k resistors. Then I read something so I hurriedly canceled my order. Then I read something else and realized I probably ordered the right stuff. So once again I need assistance @dbrn32 on this dilemma.
To dim the 2 drivers at once I need a 50k pot and 5k resistor for the lo. What wattage do they need to be?
Also, is there a better option than splicing the 2 drivers power wires to a single 3’ power cord? I mean what good is a 3’ cord. Maybe mount a junction box of some type where the connections could be made and a detachable power cord could be attached.
To be completely honest, I don’t think it matters. Pretty sure I use something like 1/4 watt.
It seems like it would be important, but I’m pretty sure it isn’t a power carrying circuit. The purpose of the resistor is just so you don’t accidentally short the dimming leads. It won’t arc, but the driver isn’t designed to be shut down that way is all. Some of the newer designs are rated for dim to zero, but not those guys sorry.
So the driver regulates the current based on what it sees at the dimming leads, you’re not trying to eat up all the power with the resistor and pot you’re installing like some of the cheesy early import grow lights had. Does that make more sense?
As far as the wiring goes, you can use whatever you’d like. All that matters is wired properly. I’ve used project boxes from amazon, standard household electrical boxes, but usually some box I have laying around at work lol. I’ve also just drilled a hole in frame, removed nut from pot, pushed through frame, and the reinstalled nut on pot. So it’s mounted directly to frame, and then put heat shrink over wiring. Up to you really.
If you want to get real cute with it, you can install a toggle switch to open both dimmer circuits too. That will actually run driver at 105-108% of rated output current. It’s like a free boost if you want it. A benefit of the B series driver only.
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Many thanks @dbrn32. The “free boost” sounds tempting as I’d like to have a on/off switch but not sure if the power boost would be a good thing in this case. Where would the toggle go? To the input side of the driver I’m guessing?
In the dimming circuit on b series drivers. If that circuit is open or showing infinite resistance they are typically at about 105-108% of rated current.
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Pictures on the internet don’t do justice to how bright COB’s are. This light is blinding. Thanks for all the help @dbrn32 with putting my shopping list together and all the useful info. As well as the other fellas for your thoughts as well. Just gotta put some hangers on this thing and get her in the tent.
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No problem! Safe to say you’re pretty happy with it? If you get some time, you know how much we like pics lol
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