knight mare
Well-Known Member
Oh my god, all the bitching is so petty. Roll a spliff and relax
DiY LEDs - How to Power Them
- Thread starter SupraSPL
- Start date
But as long as you run 50 percent load or higher there is virtually no penalty
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JorgeGonzales
Well-Known Member
Not necessarily, like I said, it's really best to look at each individual driver, at the voltage you'll be driving it at. As a rule of thumb, put as much as you can on a driver without exceeding capacity. Why buy more driver than you need, if you lose efficiency and spend more money to do it?
I mean, take a look at this 70W driver:
Running that at 50% would be crap at 277V if you live in a country where there are power factor penalties, and leaves a lot of efficiency on the table.
Now take a look at this 200W driver:
If you are running at 115V, and this driver is the closest fit for you, running at 50% is really no worse than 100%.
The same critical thinking applies to comparing the upfront cost of a super efficient HLG series vs a $7.99 eBay special. If you are running a 50W grow and losing 5% efficiency, maybe it doesn't matter, since that might only be $3 over the life of your fixture, and some extra heat to keep your plants warm in a cold climate.
So yeah, do the math for your situation, but in general the safest route is to buy an appropriately sized driver and fill it to capacity.
JorgeGonzales
Well-Known Member
I think that means not to dim below 50% for best performance.
Let me ask you a serious question, so hopefully I can learn something.
What driver or drivers would you choose to run four CXB3590 at 350ma each? And how would that compare to a 200W HLG-185H-C1400B running the same CXBs, dimmed to 25%?
Edited for clarity.
simple answer (although its not helpful to you sorry) I wouldn't run a cxb3590 at 350ma. Its way too much COB to be running at that low of an amperage.
a 10% loss in efficiency whether it comes from a less efficient cob or from a less efficient driver is a still a 10% loss (additive, multiplicative).
JorgeGonzales
Well-Known Member
Except in this case of course, it's more like a 3% efficiency loss dimming to 25%, and at least a 10% efficiency gain for the cobs running at a lower current.
Anyway, this whole conversation was confused from the beginning. For @palmetto420 it makes perfect sense to build his light once, and turn up the dimmer as his space grows. Anybody saying differently is confused.
Since you didn't answer my question, I'll give you my answer. Look at the charts three posts up. Compare an HLG-60 at 100% load to an HLG-185 at 35% load, and have your mind blown. Same damned efficiency, and a lot more flexibility with the bigger driver.
So yeah "don't dim below 50%" is good advice sometimes, terrible advice other times, and once again it's better just to look up what you want to know.
I'm not confused, he is better off building the light that he needs NOW that's tuned for optimal, rather than a light that's performing half assed. 90% of the time DIY projects that depend on adding more later never finish the later. That way he will always have lights that performs optimally, whether he finishes the project or not.
oh btw your numbers are off. I calc'd for 700ma vs 1.4ma and the estimated efficiency numbers were within one percentage points.
JorgeGonzales
Well-Known Member
The guy says he is moving to a bigger space in 2 months, I say OK. Not my problem if he is lying, I'll let you be the laziness patrol.
Building your idea of an optimal light for the space would save money upfront, but by using 4 CXB3590s at low currents his efficiency is phenomenal. The opposite of half-assed. Total waste of money if he never turns it up, but not my business.
I'm not sure which of my numbers are off. Certainly possible on this amount of sleep, but you'll need to be more specific so I can correct them.
"phenomenal efficiency" which doesn't justify the cost. You really want to ADVISE somebody to run at 350ma ? despite the future expansion plans, that's exactly what your doing. Its no wonder some people think DIY cobs are still pricey as shit.
try calculating from ground zero instead of trying to estimate percentage diffs of driver and then of the cob and comparing the diffs.
JorgeGonzales
Well-Known Member
Let's assume we are adults who can follow through with their own plans and handle their own finances without your help for a second. Well, it's cheaper and easier to build one fixture with one driver that works in multiple sized spaces, and until he turns it up to the full 200W it's also more efficient than starting with a single 50W cob running at 1400ma. There, I bolded it. Now do you get it?
And again, no idea what your second sentence means, and I'm still wondering where my numbers are off.
so why not advise him to build one single light at 50w at 1.4A and save the $$ for after hes learned how to build lights ?
my initial and only real objection to this whole thing is NOT to recommend dimming below 50% of load for normal growing conditions, because of driver behavior. Can't you incorporate that into providing good advise to led novices ?
alesh
Well-Known Member
Before jumping to conclusions, try to measure efficiency of a driver yourselves.
The key factor for HLG-C (and probably other high voltage drivers) is it's output voltage not the load. Ie HLG-185H-C1400 dimmed to 700mA@~140V will be way more efficient than HLG-185H-C1400 running at full current but near min voltage.
The key factor for HLG-C (and probably other high voltage drivers) is it's output voltage not the load. Ie HLG-185H-C1400 dimmed to 700mA@~140V will be way more efficient than HLG-185H-C1400 running at full current but near min voltage.
JorgeGonzales
Well-Known Member
But load is measured in watts, so volts and load have a 1:1 relationship on a constant current driver, as long as you stay within it's constant current voltage range.
In other words, load and volts are the same thing if the current remains 1400ma, one is just multiplied by a 1.4x constant.
alesh
Well-Known Member
Sure. My point is that there's no reason not to dim below 50% if your driver is (almost) fully utilized.
JorgeGonzales
Well-Known Member
Thank you.
Bill Lidgate
Active Member
BG Micro a Texas electronics surplus dealer is currently selling the following Mean Well LED drivers:
HLG-120H-48A LED Series Power Supply, 48V/2.5A With Connectors
PWR1427 $14.95
0.1245$/w
http://www.bgmicro.com/hlg-185h-48a...-current-high-efficiency-by-meanwell-1-1.aspx
HLG-185H-48A LED Series Power Supply, 48V/3.9A With Connectors
PWR1426 $22.95
0.1240$/w
http://www.bgmicro.com/hlg-185h-48a...nt-current-high-efficiency-by-meanwell-1.aspx
HLG-185H-48A LED Series Power Supply, 48V/3.9A With Wires Stripped And Tinned
PWR1424 $22.95
0.1240$/w
http://www.bgmicro.com/hlg-185h-48a...tant-current-high-efficiency-by-meanwell.aspx
All are bulk new stock and they report they have many hundreds to liquidate from a large scale local buyer near Garland, TX
Their shipping charges are not great and they give no discount or free ship with large Qty. but its a good deal nonetheless. For comparison Jameco sells these for $52.95 and $57.95, Mouser for $61.84 and $68.70 respectively.
HLG-120H-48A LED Series Power Supply, 48V/2.5A With Connectors
PWR1427 $14.95
0.1245$/w
http://www.bgmicro.com/hlg-185h-48a...-current-high-efficiency-by-meanwell-1-1.aspx
HLG-185H-48A LED Series Power Supply, 48V/3.9A With Connectors
PWR1426 $22.95
0.1240$/w
http://www.bgmicro.com/hlg-185h-48a...nt-current-high-efficiency-by-meanwell-1.aspx
HLG-185H-48A LED Series Power Supply, 48V/3.9A With Wires Stripped And Tinned
PWR1424 $22.95
0.1240$/w
http://www.bgmicro.com/hlg-185h-48a...tant-current-high-efficiency-by-meanwell.aspx
All are bulk new stock and they report they have many hundreds to liquidate from a large scale local buyer near Garland, TX
Their shipping charges are not great and they give no discount or free ship with large Qty. but its a good deal nonetheless. For comparison Jameco sells these for $52.95 and $57.95, Mouser for $61.84 and $68.70 respectively.
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Airwalker16
Well-Known Member
Great drivers for those willing to run in Parallel. I wish they were HLG-###H-C models!!! Bummer
OLD MOTHER SATIVA
Well-Known Member
awesome
i am ok with parallel
can i use 3590's?
would i have to buy 72 v..or would the 36 v work..?..the 48a part is confusing me in relation to cobs out there
would these work with the vero 18's i just bought?
thanks..
i am ok with parallel
can i use 3590's?
would i have to buy 72 v..or would the 36 v work..?..the 48a part is confusing me in relation to cobs out there
would these work with the vero 18's i just bought?
thanks..
Bill Lidgate
Active Member
The Mean Well HLG-XXXH-48A power supplies will power any LED (or array of serial/parallel LEDs) which need 24 ~ 48Vf iin constant current mode; so for the HLG-120H you can dial in any LED in that voltage range up to ~110w and the HLG-185H you can power any LED in that voltage range up to ~167w.
These PSs can of course power any smaller LEDs (or arrays) with equal to or less than these wattages. I'd buy the HLG-185H units (and have- 40 of them!) and add LEDs as needed.