Lighting Cobshop.net info, questions and answers

[BigSm0]

How much for 2 reflectors to my location ? @BigSm0

Probably to much. I'll check on the smallest box price but international shipping on them my be a deal breaker.

 

[BigSm0]

Sweet, would it be possible to let me know when you have the reflectors in? I think I'd like two auto cobs with reflectors if possible, or will they just be up on the site when you have them? Also is there a specific place you would advise to start reading about diy lights/cobs/ light spectrum etc.? Forgive me if I'm wrong but from where I'm sat it looks like you have taught yourself really well on this stuff, I'd love to have somewhere to start!

Sorry about the delays today. My baby girls birthday and I promised her my undivided attention.

Yes I will add the reflectors to the site as soon as they arrive. As for understanding cobs and the history there are numerous places on the net you could look. Growmau on YouTube is a good starting point. I have done a lot of work here in the DIY section as well and the completed grows are starting to flow in. Some of the technical stuff does get difficult to grasp but the basics aren't so bad with a little help. If there is anything specific you would like to understand I'd be happy to assist

 

[Habitual]

@BigSm0 I would appreciate that. As much as I like the autocob "Cob efficiency" seems relative comparatively speaking, with lower intensity (by 1/3 as per cobshop screencapture) and higher heat (double that of my 3590 temps)? Especially since the heat sink sits @ 160+°f near the cob @1050ma and my Tasty 3590 runs 80°f @1400ma. Isnt that too hot for the quoted long term lifespan and detrimental to efficiency? The whole heatsink heats right up if I dont hang a fan right above like pictured. The G tent is @ 75°f and 50%RH for reference.

Copy/paste from your page. I quoted the 24" 1/3 difference above as I dont ever get near 12 inches.

 

[BigSm0]

This is the first I have heard that temps are higher than expected and light intensity is lower than expected. I will gladly take the cobs back for a full refund. I would definitely like to retest them as every cob that leaves is tested prior to being boxed.

When comparing intensity are you using a par meter? I personally tested the 50v citizen vs the 36v Cree 3590 multiple times and my par meter registers nearly the same exact numbers. This is why I use them over the Cree which share similar efficiencies.

You brought up 3590 being 1400ma which it is. To achieve 50w it needs to be driven harder while the citizen being a higher voltage requires less amperage and is driven softer. 36v x 1.4 =50w and 50v x 1.05 = 52.5

As for the temps I would check the thermometer in the tent. I have tested them in Many situations to try and achieve numbers like you are reading now. I would have to dig it up but in an 80 degree room with zero air flow I register 130-135 degrees. Room temp compared to heatsink temp is a direct relation if there is no air flow, I would say that cob is in a space well over 100 degrees. Here is the specs for the heatsink. 55watt cob on a 57watt rated heatsink. .88cw is well within specs with a 50% efficient cob.

 

[Rhubarb Pi]

@BigSm0 I would appreciate that. As much as I like the autocob "Cob efficiency" seems relative comparatively speaking, with lower intensity (by 1/3 as per cobshop screencapture) and higher heat (double that of my 3590 temps)? Especially since the heat sink sits @ 160+°f near the cob @1050ma and my Tasty 3590 runs 80°f @1400ma. Isnt that too hot for the quoted long term lifespan and detrimental to efficiency? The whole heatsink heats right up if I dont hang a fan right above like pictured. The G tent is @ 75°f and 50%RH for reference.

View attachment 730850

View attachment 730864

Copy/paste from your page. I quoted the 24" 1/3 difference above as I dont ever get near 12 inches.

View attachment 730865

So, on my end, I run 2 AutoCobs in a 3x3 with little ventilation and no fan inside - the highest temp I've had in the room is 133, and that was after an almost full day with no tent opening.

I'm not sure why you're generating another 30+ degrees, but I would troubleshoot things further before disputing numbers with one of the best rep'd gentlemen on AFN - just my view on things.

 

[White Punk on Dope]

100% satisfaction after the sale or your money back. This cannot be beat by anyone. Maybe equaled but not beat. Go AutoCobs you rock.....

 

[Habitual]

Who is disputing anything? I was posting what I am seeing no doubt your numbers come from the outer fins of the heat sink as I see similar +/- , Better give the reading comprehension another go maybe? I Was addressing Big Smo, So kindly trouble shoot your way out of my conversation if you wouldnt mind. Best regards eh

So, on my end, I run 2 AutoCobs in a 3x3 with little ventilation and no fan inside - the highest temp I've had in the room is 133, and that was after an almost full day with no tent opening.

I'm not sure why you're generating another 30+ degrees, but I would troubleshoot things further before disputing numbers with one of the best rep'd gentlemen on AFN - just my view on things.

 

[Rhubarb Pi]

Who is disputing anything? I was posting what I am seeing no doubt your numbers come from the outer fins of the heat sink as I see similar +/- , Better give the reading comprehension another go maybe? I Was addressing Big Smo, So kindly trouble shoot your way out of my conversation if you wouldnt mind. Best regards eh

If you were addressing him only, you'd DM him - you're posting on an open forum questioning the effiency of a machine that's had No issues from users here - so frankly, I have every reason to be here and question what your intentions are.

 

[Habitual]

All cob info says high temps kill efficiency isn't that correct ? I am quoting your numbers @ 24 inches with and without a reflector! With out is 1/3 less 220 umoles vs 310 umoles with @ 24 inches. Hence my query about reflector availability!

The laser is accurate, I was asking questions not attacking anyone. I am just comparing heatsink temps immediately adjacent to the cobs on both units in my tent. As per thread title
Cobshop.net info, questions and answers

I already have two free auto cobs as I sold two locally to cover the whole cost of my 2.

This is the first I have heard that temps are higher than expected and light intensity is lower than expected. I will gladly take the cobs back for a full refund. I would definitely like to retest them as every cob that leaves is tested prior to being boxed.

When comparing intensity are you using a par meter? I personally tested the 50v citizen vs the 36v Cree 3590 multiple times and my par meter registers nearly the same exact numbers. This is why I use them over the Cree which share similar efficiencies.

You brought up 3590 being 1400ma which it is. To achieve 50w it needs to be driven harder while the citizen being a higher voltage requires less amperage and is driven softer. 36v x 1.4 =50w and 50v x 1.05 = 52.5

As for the temps I would check the thermometer in the tent. I have tested them in Many situations to try and achieve numbers like you are reading now. I would have to dig it up but in an 80 degree room with zero air flow I register 130-135 degrees. Room temp compared to heatsink temp is a direct relation if there is no air flow, I would say that cob is in a space well over 100 degrees. Here is the specs for the heatsink. 55watt cob on a 57watt rated heatsink. .88cw is well within specs with a 50% efficient cob.

View attachment 730944

 

[Son of Hobbes]

Easy fellas, let's tone 'er down and allow @BigSm0 a reasonable amount of time to address any issues and see what's going on. That much would be the fair thing to do.