3 X 220 Watt 5 Cob Lamps Replace 3 X 400 Watt Hps

[Dunge]

7 weeks of 12/12
Watered heavily and left them alone for a week while I visited the Astoria Crab and Wine Festival.

With two weeks to go plants are starting to look a little old.
The lower temps, especially night time lows, may well be playing a part.
There's also that Azamax spray to manage a mite population that bounced up to a level that a few plants were starting to get that horrific tenting effect.

Flowers on the mixed light side are looking bigger, but senescence is starting to show earlier than expected.
As this room is full of seedlings, I am looking a a variety of outcomes. Most of them are looking good for THC production.

The next two weeks should be interesting.

 

[Dunge]

Just noticed this.

 

[Dunge]

8 weeks of 12/12
COB space is looking a bit ragged. Not accustomed to so much fade.

Bud size looks ok, not great.
The room smells great, and trichs are abundant.
Harvest next week.

Talk about long in the tooth.
This side is getting old and ready to harvest.
May take a few early.
(photo failed to load twice,)

 

[Dan789]

Your grows looking good, especially the last flower, very frosty. Regarding,the replacement of the HPS fixtures, if I read your watt meter correctly your only using about half the wattage of the three fixtures you replaced so that's got to mater as you mentioned the electric bill.
Give us a heads up on the postmortem.

 

[Dunge]

Week 9 of 12/12 harvest day!

The numbers work out to a 40% reduction in power for lighting, but it looks like a bigger hit to production.

Look and smell good, but the size is nothing to brag about.
Will be back in a few weeks with production numbers.

 

[Dunge]

Ten days of drying and I don't need to wait for dry weight numbers.

Yield was VERY low.

The buds have good density and structure, good smell, and lots of trichomes.

So nice, but way too small.

40% reduction in power costs has yielded a failed harvest.

 

[Dunge]

And I'm back.
Remember, I attempted to replace HPS with some cheep ass LED units off AZ.
Well this kept happening.

COBs just going out.
At this writing I am 6 weeks into a flower cycle, and only 4 of the original COBs were working.
Don't worry for me, I have my HPS lit up again, and was just letting the COBs participate what they could.
Put every plant at risk by yanking this thing down.

By cross checking, I have determined that ALL the failures are COB failures.
How do I identify these COBs?

As I still have good drivers and fans, I am tempted to replace the COBs.

Each COB has a driver.

I need help buying replacement COBs please.

 

[Dunge]

Pulled a COB and found it wired backward.

You can see the red wire going to the negative terminal.
Is this what is burning them out?

Still can't find any manufacturers identifiers.

Looks like it got hot.

 

[Dunge]

OK friends, this is what I need.
15 replacements for these COBs.
And they need to be cheep.
These units were low low end to start with, so...
Any ideas will be gladly pursued.

 

[brazel]

Is it wired in series? Plus to negative

 

[brazel]

That's $.65 per watt.
About 1/4 the going rate from what I have seen.

This was your first clue not to buy them.

A lot of things you do are solid. The negative things I seen were LED related.

If you wanna buy more cheap COB to use with your driver, I'll send you links but we'll be back here again before too long.

I missed the part that said each COB has its own power supply, so they're not wired in series.

How high are your lights above the canopy?

Do you have a dimmable hps ballast? If so turn each one down to 200 and throw them LED away.

 

[Dunge]

Thanks @brazel.
You bring up an interesting additional oddity about these lamps.
The COBs are individually driven, but you can see in this photo that they are wired positive to negative.

Any idea what this is about?
I can only think that it is a feature of these particular emitters that they can be driven either way.
But then, why mark them +&-?

I understand you get what you pay for, but I'd rather not just throw away the remaining hardware.
What this effort brings into focus for me is how far down the learning curve I m when trying to select on LED from the variety of specifications on LEDs.

 

[brazel]

Thanks @brazel.
You bring up an interesting additional oddity about these lamps.
The COBs are individually driven, but you can see in this photo that they are wired positive to negative.
View attachment 764946
Any idea what this is about?
I can only think that it is a feature of these particular emitters that they can be driven either way.
But then, why mark them +&-?

I understand you get what you pay for, but I'd rather not just throw away the remaining hardware.
What this effort brings into focus for me is how far down the learning curve I m when trying to select on LED from the variety of specifications on LEDs.

No they can't, they're semiconductors. Electricity only flows one way

 

[Dunge]

No they can't, they're semiconductors. Electricity only flows one way

Can you explain that photo?
They all were wired this way, so it looks intentional.

 

[brazel]

Thanks @brazel.
You bring up an interesting additional oddity about these lamps.
The COBs are individually driven, but you can see in this photo that they are wired positive to negative.
View attachment 764946
Any idea what this is about?
I can only think that it is a feature of these particular emitters that they can be driven either way.
But then, why mark them +&-?

I understand you get what you pay for, but I'd rather not just throw away the remaining hardware.
What this effort brings into focus for me is how far down the learning curve I m when trying to select on LED from the variety of specifications on LEDs.

The red positive black negative.

It looks like two black wires does the red connect underneath to the negative

 

[brazel]

If they were working it had to be wired correct

 

[brazel]

Did you have a meter to check your power supplies?

 

[brazel]

Thanks @brazel.
You bring up an interesting additional oddity about these lamps.
The COBs are individually driven, but you can see in this photo that they are wired positive to negative.
View attachment 764946
Any idea what this is about?
I can only think that it is a feature of these particular emitters that they can be driven either way.
But then, why mark them +&-?

I understand you get what you pay for, but I'd rather not just throw away the remaining hardware.
What this effort brings into focus for me is how far down the learning curve I m when trying to select on LED from the variety of specifications on LEDs.

Good info here

http://ledgardener.com/build-led-grow-light/

 

[brazel]

You either have faulty power supply or your cob brunt from heat. Is there heatsink on them?

 

[Dunge]

I needed cheep COBs if I was going to repair cheep lamps.
Bought these:

That's right, 30 W @ $1.50 each
On the plus side, the form factor is identical, and the repair is tedious, but not too bad.

The fail is that the COBs blink at a greater than one second interval, with an on time of just a fraction of a second.

This lamp is very disturbing to look at with all the very bright blinking, all of it periodic, but not synchronized.

I believe that the power supply for each of these COBs is crow-baring despite the 30 Watt rating.
I note here that the power supplies are all wired with red being negative and black positive, so inaccuracy in labeling is not a big surprise.

My "Kill A Watt" meter reports .75 KWH used in the last 17:45 hours.
This pencils out to 42 watts per lamp that was expected to use 150 watts (30X5).

But no overheating problems!

Have not yet decided if these are worth modifying the remainder.

The COBs themselves are fantastically bright, when on.