Off the shelf retail store screw-in LED and CFL bulb comparisons

[PCBuds]

A single segment works just fine at 12 volts.

I'm sure that they are the same segments as your 12-volt strips.









What's all this 3-4 Volt forward bias voltage crap about??

They're just trying to keep people like 'Me' from making coffee with their light bulbs. Lol

 

[PCBuds]

I always question the numbers,

You don't know what to believe.

 

[PCBuds]

I checked the voltage on one LED segment while the bulb was running and got this.

I figured the only way to find out the real voltage on each segment was to measure it while it was running.

That turned out to be difficult because the light was beaming me in my face and it was hard to put the probes in there and measure the voltage.

So I taped off of all the segments except the one I was measuring.

I should have maybe put tape on the segment I was trying to measure so I could see but I didn't think of that at the time.

[URL=https://i.postimg.cc/0yL4P0nH/20191021-181215.jpg]View Image[/url]

7.28 volts DC per segment.

I'm building a 120 V full-wave bridge rectifier circuit with voltage regulation. (4 diodes and a capacitor).

[URL=https://i.postimg.cc/9XbyGP4R/Screenshot-2019-10-22-00-36-29.png]View Image[/url]

I need to check the output voltage of my circuit. It'll be a bit less than 120 V due to inefficiencies in the diodes and capacitor.
(waste dissipated as heat).

120÷7.28= ~ 16.5 segments.

I just need to build a few simple parts.

At the time, I didn't know about the resistor/fuse and that the real voltage is ~100 V DC.

So 100÷7.28 is around 14 segments.

I don't understand why they are rated ~ 3-4 V when they need 7 V just to start glowing.

f-e mentioned an RMS value and pulsing DC but none of the numbers seem to add up.



I noticed when I measured the voltage on the running bulb that the segment was a lot brighter than when I put 7 V DC to the segment.

I remember from electronics class the RMS is √2÷2=0.707.

I think my meter measures the RMS value (sort of an average value) so the real peak voltage on the segment was probably 7.28 ÷ 0.707=10.3 Volts peak.

That's way over the rated 3-4 volts.

 

[PCBuds]

120vac is RMS, or rather 70.7% of the peak. After rectifying, and smoothing, it's this peak you will be left at. Presuming the capacitor can carry you from one to the next, without so much ripple the lights flicker. So you can expect ~150vdc.

Something is off with the led voltages. I can't see what, but it doesn't sit right with me. Even seeing you prove one with 12v, leaves me doubting it's 12v.

I know. The numbers don't add up.

 

[PCBuds]

This quote is quite helpful.

Be careful comparing these domestic lamps to strips as 1521lm, because they're not after pulling the dome off. Earlier we looked at the light transmission of these domes, and found the true lm/w figure to be more like 175lm/w, as supported by our own testing, not just the maths. Since then, the new one's have been released, 15% brighter.

It's the generation game. We started here with 17w 1521lm lamps, then 14w 1521lm lamps, and now it's 12w 1521lm lamps. That is 126lm/w through a diffuse dome with perhaps 70% light transmission. Giving us something more like 180lm/w from the leds, which are in turn perhaps 200lm/w leds being pushed too hard to achieve full efficiency. Picked from the same parts catalogue that everyone has access to, with similar budget restraints.

The strips won't be double the output. 126 x 2 is 254, but the strips are 180 at the test current. That is under 50% more, and we havn't took the dome off yet, or over driven the strips. I think the gap will close until we realise it's just leds in different packaging.

Even if you jump ship to known 220lm/w samsung QB's, they are over driven to 180lm/w in most fittings. There is no huge gap between anything, just as long as it's a recent design, that must compete with other brand leaders.

I have these screw-in lamps. Citizen cobs. QB's. Some smart cob junk to, and corn lamps that are a joke. I haven't found the screw-in's to be lacking beside the citizens v6 1212 or Samsung lm301b. But they trash the 100lm/w smart cobs, which there 14w 1521lm/w figure puts them beside. It's that globe.. It really lets them down.

 

[Drop That Sound]

So the drivers self adjust as they get hotter? Does that mean trying to cool the SILs off better will drive them harder, and actually further reduce the life span than making them last longer?

 

[PCBuds]

Yes, the built-in driver in SILs automatically adjusts the current/voltage.

If you cool them the driver just adjusts to the temperature and keeps the LED segments at a consistent output.

Heat is never good though but the SILs are designed to deal with it so going to great lengths to cool the bulbs isn't necessary.

Removing heat from your grow area is more of a concern if you have many bulbs in a small space.

 

[noknees]

So the drivers self adjust as they get hotter? Does that mean trying to cool the SILs off better will drive them harder, and actually further reduce the life span than making them last longer?

Terp air-cooled his a while back, and following his lead wouldn't be terrible idea.


https://www.icmag.com/ic/showpost.php?p=8534536&postcount=337




anecdotally, i've already had bulb failure (100w ec0smrt) in a low-hour recessed kitchen fixture. upon removal, lettering on the base was smeared. too much heat...?


longevity+performance aside, i'll air-cool mine in the future just for a modicum of peace of mind/safety. bit of a pain in the dick, but 100% worth it to me to rest a bit easier.

 

[PCBuds]

Some of my bulbs say this.







Others say this.




I guess you can enclose these ones in a fixture?





But they're only 10-watt bulbs.
I would think everything over 14 watts would need to be at least vented in some way.

 

[PCBuds]

longevity+performance aside, i'll air-cool mine in the future just for a modicum of peace of mind/safety. bit of a pain in the dick, but 100% worth it to me to rest a bit easier.

That's my biggest concern.

I'd like to think that the bulbs would simply burn out and if there was any chance of fire then the bulbs would have been recalled and not allowed on the market regardless of how they're used.

 

[Douglas.Curtis]

So the drivers self adjust as they get hotter? Does that mean trying to cool the SILs off better will drive them harder, and actually further reduce the life span than making them last longer?

Simple answer, yes to the driver, no to the LED. The LED is just fine.

Long answer, you're actually driving the ballast harder. The cooler you keep the chips, the harder the driver has to work to keep the chip at peak operating temp. This produces additional heat, while using additional electricity.

The exact same thing happens, when you keep T5 lamps below about 95F.

 

[PCBuds]

I wonder if noknees' dead bulb has a dead ballast or dead led segments, or both ?

 

[indagroove]

Thinking about trying one of these out..

https://www.amazon.com/arrival-spectrum-CXB3590-grow-light/dp/B07V3LF2GH

 

[PCBuds]

Thinking about trying one of these out..

https://www.amazon.com/arrival-spectrum-CXB3590-grow-light/dp/B07V3LF2GH

View Image

I don't know dude, single source of heat, single source of light, I'm going to try the opposite.




I just got a tie them off and plug them in.

 

[indagroove]

I don't know dude, single source of heat, single source of light, I'm going to try the opposite.

[URL=https://i.postimg.cc/xj47DnsM/20191112-153227.jpg]View Image[/url]


I just got a tie them off and plug them in.

Yeah, in my experience single sources penetrate deeper with lower lumen drop off based on distance from the source. Currently I use a 600w hps in a 4x4 area, but looking to switching to a 315 cmh plus 200w of LED supplement. There are some other screw in cobs @ 40watts I was looking at too. Five of those plus the 315w CMH would be enough to compete with the 600w hps, and would be lower wattage.

 

[PCBuds]

You have yet to show us a pic. of your grow.

Show us what works for you.

 

[indagroove]

You have yet to show us a pic. of your grow.

Show us what works for you.

Here we are towards the end of a run, partial tent shot of two plants in a 4'x4' tent under 600w hps for 7 weeks of 12/12, then 400w cmh for the last two weeks. Up to 400cfm variable exhaust in an aircooled hood in a 4'x4' tent, with a couple circulation fans. Nothing fancy really. I didn't veg this run as long as I should have, because it was originally planned to be a 6-plant run, but the other 4 clones turned out to be taken from a genetically defected mother, so I canned them and just ran with these two plants with one extra week veg. 600w hps always delivers solid, but like I said I want to move to a mixed light situation with cmh and led. I currently have a cheap 4x cob system I sometimes use for veg, and have also flowered under it. The footprint really only covers 2x2 for flowering, but the canopy penetration and lumen dropoff is much better than lower wattage light sources based on my measurements.

 

[indagroove]

These SILs with a cree chip driven at 40w seem pretty nice..

https://www.amazon.com/dp/B07T47G2L2

The down side is the cost to buy 5 of them.

 

[Hookahhead]

Flower shot looks nice. The lights looks like they’re intended for the cannabis market, which likely means a higher markup. Try to find who manufactures the non branded version.

The room I want to hang the 3x3 needs a lot of work. I’m running out of room over here, somehow I just can’t find any free space. I can’t easily raise the light any higher either. Luckily most of the larger ones are moving to a friends farm by next weekend. They’re definitely ready to get out of those pots.

Here’s the new 3x1.5ft clone shelf, running on 36w. Total setup is now 192w.

 

[Hookahhead]

I currently have a cheap 4x cob system I sometimes use for veg, and have also flowered under it. The footprint really only covers 2x2 for flowering, but the canopy penetration and lumen dropoff is much better than lower wattage light sources based on my measurements.

I’m not sure how much space you have under the canopy, but have you ever considered giving under canopy lighting a shot? For me it’s one of the most interesting applications of SIL or LED bars. There was a university study recently published that showed impressive yield and potency boost in cannabis with LED under lighting.

https://atrium.lib.uoguelph.ca/xmlui/bitstream/handle/10214/14294/Hawley_David_201809_phd.pdf?sequence=5&isAllowed=y