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The facts about CO2 ppm: don't use 1,500!

headees

Active member
I agree, that was a great and helpful post by Player2. And I bet if you posted pictures of the 'guts' of your controller people here may be able to help you. I assume Digigro is not being honest, and you can adjust their controller. It sounds like they are trying to force you to buy a new controller by not telling you the truth. But I could be wrong ...

Yea thats what I was getting at, seems they just want to sell me another fix rather than help me modify the one I have. Im going to call them and see if I can get a more detailed reason as to why I cant change the setting on their controller.
In the meantime I did get some gut shots of the Digigro Coco. If anyone can make head or tails of the schematic and let me know if I can mod it to get 900-1100 intead of 1200-1500 that would be great.
Could that removable chip at the bottom of the board of the first pic be the same kind of "jumper" that you mod the other controller with? Looks like you can plug it into any of those slots in that row.
I have no idea what Im talking about if thats not totally obvious :)

BTW Spurr thanks so much for all you are contributing here. Its good to have someone who has a wealth of info backed by hard science on this site.


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Great, thanks for the info. What type of cultivar (re genetics and parents) is the "Flav"?

The Flav is the real deal Romulan x BCGA Space Queen (Romulan x C99). So basically a Romulan backcross. The breeder isn't very well liked here on IC, but his gear is killer.
 

Player2

Member
Sorry spurr for dragging this thread all over the place. If this needs to go somewhere else, make it so!

so,
Everything is possible. Looks like you(and whoever else has that unit) have an S-100 or S-100H sensor.
http://www.elti.co.kr/new/eng/carbon-dioxide-module-s-100h.htm

The quick answer, one of the output signals is "Analog Voltage Output VDC 0.5 ~ 4.5V (linear output)" meaning any circuit with an adjustable voltage threshold could be cobbled together to work... with a bunch of screwing around.

Better news is that the board is probably also adjustable. Could you take a better picture of the pins at the bottom of 008nwp.jpg?
Could you take another pic of 010hqk.jpg so that I can see between the white connector and the jumper?
Could you just take a bunch more pictures of it and the sensor?

Remember, I(we) need to be able to read what is printed on the board.

It might also help is you remove the sensor daughterboard. It is either held on by the friction of connectors or fastened from behind. Try taking out the 2 phillips and removing the board from the housing and taking a look. If it is soldered together, forget it.

I'm pretty sure the device is tough, but always a good idea to static strap yourself to the same potential. Don't go wearing your favorite batman pajamas with those plastic feet and run around on the carpet before doing this.

This is only a possibility. I am not saying that I will get to the bottom of this, but I will take a look.

Another thing, we vote with our money. Like being able to mod stuff and have product support that shares what they know with you instead of keeping secrets and just trying to sell you new stuff? Don't put up with it. Call them and tell them why you aren't buying their stuff anymore. Send emails. Then buy from good companies and call them and tell them why you are buying.

Both of these units output so that a computer can read them. If I don't get sidetracked from this sidetrack by my other sidetracks I might get this logging on the computer.
 

spurr

Active member
Veteran

spurr

Active member
Veteran

spurr

Active member
Veteran
@ All,

I thought some folks might like to read this paper, wrt increased CO2 and increased UV-b. If so I can upload it at some point.

It's pretty well proven high UV-b daily net irradiance of ~5-13 kJ/area^2/day UV-bbe will increase THC in leaf and inflorescence, quite a lot. I too have tested UV-b for some time at ~10 kJ/area^2/day UV-b, not UV-bbe (yet), and found via Thin Layer Chromatography and spot density analysis and comparison that UV-b did increase THC (thus did THC-A).

The growth reduction from UV-b comes from a few issues, all of which are out of context of this thread, however, "crytochrome" should give people a good research term. It's important to provide sufficient UV-a and PAR range irradiance to prevent possible negative effects on plant cells from UV-b. Also, UV-b irradiation increases UV-b screening secondary metabolites in plants, e.g., some terpens and flavonoids (i.e., "anthocyanin", which colors leafs and inflorescence purple, red and blue colors).

Effects of increasing UV-B radiation and atmospheric CO2 on photosynthesis and growth: Implications for terrestrial ecosystems
by J H Sullivan
Plant Ecology, Vol. 128, No. 1-2, pp: 194-206 (1997)

Abstract:

Increases in UV-B radiation reaching the earth as a result of stratospheric ozone depletion will most likely accompany increases in atmospheric CO2 concentrations. Many studies have examined the effects of each factor independently, but few have evaluated the combined effects of both UV-B radiation and elevated CO2. In general the results of such studies have shown independent effects on growth or seed yield. Although interspecific variation is large, high levels of UV-B radiation tends to reduce plant growth in sensitive species, while CO2 enrichment tends to promote growth in most C-3 species. However, most previous studies have not looked at temporal effects or at the relationship between photosynthetic acclimation to CO2 and possible photosynthetic limitations imposed by UV-B radiation. Elevated CO2 may provide some protection against UV-B for some species. In contrast, UV-B radiation may limit the ability to exploit elevated CO2 in other species. Interactions between the effects of CO2 enrichment and UV-B radiation exposure have also been shown for biomass allocation. Effects on both biomass allocation and photosynthetic acclimation may be important to ecosystem structure in terms of seedling establishment, competition and reproductive output. Few studies have evaluated ecosystem processes such as decomposition or nutrient cycling. Interactive effects may be subtle and species specific but should not be ignored in the assessment of the potential impacts of increases in CO2 and W-B radiation on plants.
 

headees

Active member
Sorry spurr for dragging this thread all over the place. If this needs to go somewhere else, make it so!

so,
Everything is possible. Looks like you(and whoever else has that unit) have an S-100 or S-100H sensor.
http://www.elti.co.kr/new/eng/carbon-dioxide-module-s-100h.htm

The quick answer, one of the output signals is "Analog Voltage Output VDC 0.5 ~ 4.5V (linear output)" meaning any circuit with an adjustable voltage threshold could be cobbled together to work... with a bunch of screwing around.

Better news is that the board is probably also adjustable. Could you take a better picture of the pins at the bottom of 008nwp.jpg?
Could you take another pic of 010hqk.jpg so that I can see between the white connector and the jumper?
Could you just take a bunch more pictures of it and the sensor?

Remember, I(we) need to be able to read what is printed on the board.

It might also help is you remove the sensor daughterboard. It is either held on by the friction of connectors or fastened from behind. Try taking out the 2 phillips and removing the board from the housing and taking a look. If it is soldered together, forget it.

I'm pretty sure the device is tough, but always a good idea to static strap yourself to the same potential. Don't go wearing your favorite batman pajamas with those plastic feet and run around on the carpet before doing this.

This is only a possibility. I am not saying that I will get to the bottom of this, but I will take a look.

Another thing, we vote with our money. Like being able to mod stuff and have product support that shares what they know with you instead of keeping secrets and just trying to sell you new stuff? Don't put up with it. Call them and tell them why you aren't buying their stuff anymore. Send emails. Then buy from good companies and call them and tell them why you are buying.

Both of these units output so that a computer can read them. If I don't get sidetracked from this sidetrack by my other sidetracks I might get this logging on the computer.


Ok finally got a chance to take some more pics. I was weary about removing the sensor, but tried to get detailed pics as possible around the space of daughterboard.
If anyone can help me get this thing recalibrated I would really appreciate it.:)

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Player2

Member
Hey headees,

I can't see the traces and can hardy read the board. Sorry.

If I had to guess, JP1, the jumper by the white connector is the variable analog output of the sensor, for testing the unit.

I would guess that the headers J3 and J4 are where the money is at, if they designed in that functionality. This isn't even for sure yet. Without them telling, who knows.

That chip has an auto and manual calibration. Jumper the manual calibration without knowing what you are doing and it is essentially bricked. Soooooo no fun just connecting things and seeing what happens.

Call that company and bitch. Demand they send you the info they have. Tell them about this thread. Tell them about the other co2 controller you will be buying and what kind you will tell everyone not to buy. Tell them you will make accounts on every gardening board just to bad mouth their stuff. Disgruntled customers can be mofos. You just gotta prove it!
 
I have the Digigro COCO as well as a 2 of their other products and have been quite pleased with them. I forwarded some of this thread to them and asked about moving the setpoint. Their response:


Interesting read, nice to see that the online community is getting away from wanting 1800-2000ppm setpoints which was the most popular request last year, also due to compelling evidence in a forum posting.

Unfortunately, we are unable to move the relay setpoint on the COCO controller. It is a fixed point controller that is programmed at the factory to our specifications. While a movable setpoint is a desirable feature, it would come at the expense of what we felt were more desirable features.

The COCO is currently the lowest price NDIR Co2 controller on the market and the only one of the new generation sensors that includes a digital readout.

In selecting the fixed points for the COCO, we settled on what was considered the industry standard of 1200-1500ppm. This was after much research into the science as well as the target market itself. We actually raised the 1200 floor to 1300 in response to the market. If we released the COCO with a 1000 ppm setpoint, I would likely be sitting in a warehouse full of unsold product instead of delivering our 400th COCO controller this week. That said, should we see a demand for a 1000 ppm setpoint controller, we are in a position to be the first to market with it.

Knowing our fixed point COCO wouldn't fill everyones needs, we also offer a Telaire based controller. The Telaire sensor has a movable setpoint and deadband. The analog outputs are also very configurable, making it a first choice for integrating into computer controlled systems.

*****, I appreciate your bringing this to my attention. I hope in our dealings, you've come to know us as a very service oriented business. We are hobby growers ourselves and can sit and talk shop all day with our customers. We love this industry and have literally waited a lifetime for it! We want all of our customers to have success with our products and will go the extra mile for them.

If there's a customer on the forum that feels that they need an adjustable controller, we would be happy to upgrade them to our Telaire based unit for the difference in the retail price, which is about 50 bucks. If I had the opportunity to discuss this customers needs, we would have made this offer to them when they contacted us. I can assure you our longterm goals aren't achievable through deception, only great service!



-------

I fried my first controller right out of the box by plugging a sump pump into it, they replaced it at no charge and sent me the more expensive version at no charge so I have had good experiences with them.
 

TheDillest

New member
Thankfully I paid the extra dollar for the Sentinel controller which allows me full control of my CO2 from 0ppm to 2500ppm

I am intregued by the articles you present here but I find there is one problem with it

The studies compare the effects of 1200ppm to 2500ppm and clearly demonstrate that 2500ppm has detrimental effects on C3 plants.

This however does not prove that 1200ppm is the saturation point and that 1500ppm would also cause detriment.
Unless the study were to have used another group of plants at 1500ppm I don't see how we can correlate the negative yield from 2500ppm to 1500ppm.

I have currently set my controller to turn on at 1000ppm and it usually peaks at around 1150ppm, but I will be switching it back to 1500ppm if I cannot find any evidence that this is also toxic.

Just because 2500ppm is toxic doesnt mean 1500ppm is, unless i missed something
 
I had a hell of a time trying to dial my environment to 1500/85degrees/50%rh. I find things run smoother at 75-80 which negates the demand for higher co2 levels. I still run at 1500 on one controller and 1000-1200 on another.

I do have to say i would never go back to normal levels. Results speak for themselves.

there was a blurb about a new model they are working on that will datalog your environmental levels so you can see hour by hour what is going on in your cea space.
 

k1k1

Member
I had a hell of a time trying to dial my environment to 1500/85degrees/50%rh. I find things run smoother at 75-80 which negates the demand for higher co2 levels. I still run at 1500 on one controller and 1000-1200 on another.

I do have to say i would never go back to normal levels. Results speak for themselves.

there was a blurb about a new model they are working on that will datalog your environmental levels so you can see hour by hour what is going on in your cea space.

Hi !!
Do you mean you prefer 1000PPM than 1500 ??

For best results and/or environment control facility??

All the best

K1K1
 
Hi !!
Do you mean you prefer 1000PPM than 1500 ??

For best results and/or environment control facility??

All the best

K1K1

In that particular space it was very difficult to balance the equipment at 85. the temp rh swings were hard to control.

My point was rather than pick a target like 1500, look for the sweet spot within your range. For me that's anywhere from 800-1500.

You'll get better results if your environment is dialed. Mine runs smoother at 78-82 and 1000ppm.
 

Grobot2010

Member
OP: All of your cited studies are done on wheat and/or rice and none of them show the temperature dependence of the optimal CO2 concentration, which gives me two reasons not to give them much credence when growing marijuana.

Given the fact that the growers here are interested in marijuana, I'd take these results to be worth a grain of salt (or should it be a grain or rice in this case?). The optimal concentration for marijuana is 1500 ppm (and the grow temperature should be adjusted upward, accordingly).

Simply by looking at the plant mass to surface area ratio in wheat and/or rice versus marijuana tells me that it is not the model system to use in making accurate predictions about the optimal atmospheric CO2 concentration for maximizing crop yield.
 

Dorky

Member
In that particular space it was very difficult to balance the equipment at 85. the temp rh swings were hard to control.

My point was rather than pick a target like 1500, look for the sweet spot within your range. For me that's anywhere from 800-1500.

You'll get better results if your environment is dialed. Mine runs smoother at 78-82 and 1000ppm.



78-82 and 1100-1200ppm

Is what I have found works best too without stressing my girls.
 

eL artist

Member
so looks like i need to buy a new co2 controller so i can do the exchange betweeen my two rooms one on night while other is day and that means cant get up to 1200ppm looks like need to stay more in 500-700 so there is no detremental effect to night ladies, oh well just going get the fuzzy logic cap ppm 2a, cheaper than buyin another a/c and dehumidifier

I am so happy i found this thread thank you spur
 
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