Measuring light and power consumption

So I’ve finally finishing building my lights and I don’t think I’m adding any more to them. They’re all strips and boards. Used to have some smaller cobs in there but I replaced them with two f564bs. The light also has two boards and two strips from this company called Atreum as well. They’re really nice and have 301b chips in them. I finished installing the f564bs this evening so now it has two of those, and in theory it maxes out at about 480 watts (3 different drivers — a 240h-54b for the boards, a 120h-54a for the pre-built strips, and a 120h-48a for the f series strips).

Now that I have these lights I’m trying to learn more about how to use them most effectively. I have a light meter and I’m about to order some kilowatt meters to measure power consumption in real-time.

So obviously I want to dial these lights in so I get a really good yield. They’re spread out perfectly over the canopy now and I can drop it down really low, kinda like I have it now for veg. I’m still new to all this and now I feel like I need to learn more about measuring the light output and power consumption and figure out how to set them so I get a big yield without a huge electric bill.


This is the light meter I bought. I haven’t really messed with it much yet and I’m still not quite sure how to make use of the readings I get. Obviously I want to measure light at the canopy but I don’t know how translate the readings on the meter into an idea of the PAR my light’s putting off.


The goal is to run the light at the lowest power possible while still getting nice dense buds. If anyone can give me a brief explanation of how to translate the readings on the light meter and point me towards some good reading on the subject I’d really appreciate it.

https://www.rollitup.org/t/lux-to-par-to-ppfd-conversion-charts.883209/

It's in here....

Somewhere between 700-900 PAR is going to give you optimal growth with minimal power consumption.

Some of the links in there are busted...
There used to be a collection of LUX conversion numbers floating around here...for a bunch of different emitters.

Here's a treasure trove of knowledge, for when you really, really, wanna get your nerd on....https://www.rollitup.org/t/math-behind.868988/

Terrapin, good fucking work, buddy. That light turned out so sick!!

Airwalker16 said:

Terrapin, good fucking work, buddy. That light turned out so sick!!

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Thanks! You helped me a whole lot while I was learning and building. @coreywebster too. Both of you gave me some great advice and helped me to get this project done faster and of higher quality than I would have been able to with no help. I’m really satisfied with how it came out. I got so excited when I realized I could replace those weak old 1820s with the f series strips and keep the same driver and wiring. Now it’s the light it was always meant to be.

What I don’t know, and what I think is a real deficiency at this point, is how to accurately measure the light with my meter and how to convert lux to a reasonable representation of PAR. The goal now that this light spreads out over the whole canopy is to get maximum yield with minimum power consumption.

Chip Green said:

Here's a treasure trove of knowledge, for when you really, really, wanna get your nerd on....https://www.rollitup.org/t/math-behind.868988/

Click to expand...

Thanks. I haven’t clicked on the link yet but that’s exactly what I want to do now — get my nerd on. Now that I have the light I want to thoroughly understand the process of how to set the light for maximum photosynthesis.

Edit — just took a look at that and it’s kinda overwhelming. I never did well in college because I can’t absorb big pages of raw information really well. Sure all that is good to know, but I’d need a couple semesters of physics classes to really be able to understand all that.

That said I was always great in the lab, and once I could actually see all that stuff work in real life I picked it up right away. I just need a cheat sheet, sort of. How to use the meter, take the readings, and use them to set my light up in the most efficient way possible.

nice build, congrats!

you can try this converter to help you getting the picture.

have to say i dont trust the my lux meter readings that much, at lest my luxmeter seems to be not very precise.
you can compare yourself, this pattern goes on.

cobshopgrow said:

nice build, congrats!

you can try this converter to help you getting the picture.

Convert Lux to PPFD - Online Calculator | Waveform Lighting

Online calculator to convert illuminance (lux) to PPFD (micromoles per second per meter squared).

www.waveformlighting.com

have to say i dont trust the my lux meter readings that much, at lest my luxmeter seems to be not very precise.
you can compare yourself, this pattern goes on.
View attachment 4459287

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315 to 4230 difference??!!

3150 to 4230, there is a zero you miss on the picutre above.

thats no precise number, but i had this pattern under pretty much any light source and spectrum.

cobshopgrow said:

nice build, congrats!

you can try this converter to help you getting the picture.

Convert Lux to PPFD - Online Calculator | Waveform Lighting

Online calculator to convert illuminance (lux) to PPFD (micromoles per second per meter squared).

www.waveformlighting.com

have to say i dont trust the my lux meter readings that much, at lest my luxmeter seems to be not very precise.
you can compare yourself, this pattern goes on.
View attachment 4459287

Click to expand...

This is a fantastic post my friend. Hopefully more can see it.

^ @Airwalker16 that's 3150 actually, so it's a ~1100 difference.

I have the very same lux meter and I've known for 100% sure that the reading was way too low. 30k lux in veg wrecks your plants, across the board. I wouldn't be surprised if different meters of the same model give different readings either.

I have a PPM pen that is supposed to be 0.5 scale but 0.28 in reality- of course it is totally unreliable. Cheap tools make cheap measurements! Watch your plants, before you look at that number...

glad it helps you ! and maybe others.

"30k lux in veg wrecks your plants "
great info, as i encountered the same.
I already doubted myself before i got the spectromaster.

i can also confirm the PPM pen story at least the 3$ are crap , from 10$ ppm/ec switchable ones, it gets way better.

one more, daylight, window.

I been using the good ol' Dr. Meter since I got into this scene around three years ago...
I know it's readings will not be completely accurate in comparison to the top quality devices, but I care not.
What it does provide is a standard for my builds...
I don't give a frogs fat ass what my actual PAR is....
The readout from the Dr. , is a useful guide to emitter spacing, and hanging levels.

TerrapinBlazin said:

overwhelming.

Click to expand...

TerrapinBlazin said:

semesters of physics

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Yeah there's discussion going on there that I could never, ever get my mind around.... kinda neat to know there's dudes like that out there though....

I concluded eventually, that those insane formulas prove that my lights kick ass.

Chip Green said:

I been using the good ol' Dr. Meter since I got into this scene around three years ago...
I know it's readings will not be completely accurate in comparison to the top quality devices, but I care not.
What it does provide is a standard for my builds...
I don't give a frogs fat ass what my actual PAR is....
The readout from the Dr. , is a useful guide to emitter spacing, and hanging levels.

Click to expand...

Yep, same meter i have, works fine, allows me to get a rough idea on whats happening across the canopy and helps me keep things consistent

nothing wrong taking a luxmeter to work with the values.

problem arises when you take the 30k lux for veg max rule and your plants get more like 40k and burn,
while youre qeustioning yourself why, cause internet said its fine.

as long you know it, its all good, i needed to spend quite some money to get my head around it

btw could be that the dr.luxmeter behaves better then the one "we" used.

I’ve got the orange Dr. Meter as well. Seemed like the best value.

It’s funny someone mentioned burning from too much light. I thought it was mag deficiency until I looked at the lights from directly underneath and saw they were way brighter than I thought. These strips and boards are deceptive. I was only seeing about half of the light looking at it standing up. I wondered why the tips were getting chlorosis and the insides of the plants were getting dense and bushy af. It all makes sense now and I turned them WAY down, but that realization is what inspired me to make this thread.

What has really been intriguing to me, is the physical difference in plant growth structure, from the DIY LED builds, in comparison to CHM.
I have a really good horse, a gifted cut of LA Chocolate I have been running for a couple years....looks like a completely different plant when I run it under CMH vs the BXEB units....

So, for instance, how would I make use of this reading here? I have it measuring at x10 and it reads approximately 1000. Does that mean 10000 lux and that I should drop the light/turn up the drivers? That number should be closer to 3000? There’s no easy lux to PAR conversion formula?

Man I’m gonna have a whole new set of questions when this light burn heals and it’s time to flip these.