Hm i think i just would look at the Amps consumption. How much does the noctua take compared to the 120s? Hehe i have a noc+heatS. on my cpu. My 1€ ebay 140s use about 0,37A, i have much smaller fans that take much more and they are louuuud. I think i will have to watch the temps and see if its ok. But im going to use far less than 400W, so i hope i will be ok. Do you run them @ 12V?
JMD's #2 Indoor grow (hydroponic)
- Thread starter JMD
- Start date
Positivity
Well-Known Member
Nice! Frosty and green! Those xpgs kick butt apparently
Hey JMD, im going defenitely to use metal Sheets to cover my heatsinks fins. What i wonder, I have like 9 Led Drivers that Im going to use lol, while I could put them on top of the heatsink, I dont want to have the "mains" anywhere near me or while working with the light. Is that a reasonable concern? On that other Hand that will force me to have like 9x2 ->18 wires going from my "device"...Im thinking I should use a PC Mainboard ATX -Power connector? It has like 24 wires, for easy plug an Play, im thinking. But im find it rather hard to obtain, atleast the "female part". Or do you maybe have a different idea for a connector?
JMD
Well-Known Member
Sounds like a good idea to do it that way - you want to keep mains away from your working area. Remember that the drivers might get hot, so make sure that they are not just put in a big pile
You can search eBay for the parts you need (search for "atx female").
Small update on the design of a LED driver: The topology I'm going to use, will be a self-oscillating resonant driver. It will switch at a frequency in the range of 20-150 MHz, with an input to output efficiency at around 90%.
This topology is a quite a bit more advanced than for example a simply driver based on a forward-switch or a flyback, but it should also be quite a bit better. Time will tell
JMD
Well-Known Member
Those CC drivers you are talking about, are just buck converters. By other words: They are purely DC/DC - this is possible to do at high efficiency. But you need a DC voltage source, which also have losses.
So let's your AC to DC conversion is 95% efficient, and your Meanwell DC/DC is also 95% efficient.. input to output efficiency is then a combined 90%.
Other advantages are the life time. Traditionally you would need a couple of electrolytic capacitors, which only lasts a few thousand hours when they get hot. The higher the frequency, the lower capacitance do you need. This mean you can use small SMD ceramic capacitors instead - these lasts quite a bit longer, and takes up much less space.
Normally when building a converter connected directly to mains (AC), you use a transformer to step down the voltage. You also need an inductor for the DC/DC switching. All these are specially wound, with special core material and with EMC shielding etc. This design I'm going with only utilizes SMD air core inductors. No core material needed or rare earth metals needed.. just air.
I will try to reduce the price as much as possible.
JMD
Well-Known Member
As you see with many cheap Chinese LED lamps.. they die way too quick. And of course as you mentioned yourself - a lot of EMI
JMD
Well-Known Member
Time for an update! Growth completely stopped some weeks ago, but there's been a massive production of crystals and flower sites instead 
I did the last feeding (or what I expect to be the last) a couple of days ago, where I added a bit of MgSO4 and 3:5 of the A:B nutes. PH got adjusted down to about 4.5, which yielded 5.0 when mixed in the reservoir.
I expect to harvest in 1-1½ week (maybe even 2, since some hairs are still white). What do you guys think?
I did the last feeding (or what I expect to be the last) a couple of days ago, where I added a bit of MgSO4 and 3:5 of the A:B nutes. PH got adjusted down to about 4.5, which yielded 5.0 when mixed in the reservoir.
I expect to harvest in 1-1½ week (maybe even 2, since some hairs are still white). What do you guys think?
PetFlora
Well-Known Member
Plants look amazing
I go up in pH during mid-flower (hydro) (~5.9- 6.1)
That's where P and Mg kick in
View attachment 2890468
I go up in pH during mid-flower (hydro) (~5.9- 6.1)
That's where P and Mg kick in
View attachment 2890468
JMD
Well-Known Member
Thanks mate! Amazing strain so far, with a ton of trichomes everywhere - can't wait to try it out!
The reason why I drop the pH that much, is because it rises very fast. In a about 2 days it can go from 4.0 to 8.5.. that's rather fast, right?
But I've done this grow with the aim to see what results you can get, while doing very little work. I add nutes, water and adjust pH once a week. I didn't do any trimming of any kind. So even with a rather busy schedule, the work load is very manageable.
I've been using this lockout chart:
View attachment 2890792
JMD
Well-Known Member
Not really sure how to figure out whats causing the rapid rise in pH.
Slipon
Well-Known Member
all the Lime in out tap water, if you want to continue to grow in Hydro I would suggest you to look in to a Reverse Osmosis filter system
http://espwaterproducts.com/about-reverse-osmosis.htm
[video=youtube;rG29fwWoNkc]http://www.youtube.com/watch?v=rG29fwWoNkc[/video]
http://espwaterproducts.com/about-reverse-osmosis.htm
[video=youtube;rG29fwWoNkc]http://www.youtube.com/watch?v=rG29fwWoNkc[/video]
JMD
Well-Known Member
If that's the only way to stabilize the pH, I don't think I'm going to buy it - it would increase the cost of the setup by about 100% !
So far it has been working fairly okay without RO water
(would of course be nice to increase the yield)
PetFlora
Well-Known Member
Like everything else, not all ROs preform equally.
As with leds their capabilities are WAY oversold, based on lab parameters, not typical tap water
Water pressure is important as well as RO membrane rejection parameters- most of the <$500 are a total joke. Mine cost > $1700 over 10 years ago.
Filters, which one you need depends on what's in your water. The wrong one will quickly destroy the RO membrane
As with leds their capabilities are WAY oversold, based on lab parameters, not typical tap water
Water pressure is important as well as RO membrane rejection parameters- most of the <$500 are a total joke. Mine cost > $1700 over 10 years ago.
Filters, which one you need depends on what's in your water. The wrong one will quickly destroy the RO membrane
JMD
Well-Known Member
I'm definitely not going to pay 3 times more for RO system than rest of the system has cost. At least not right now with my 60x60cm cabinet