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KonopCh

Well-Known Member
im pretty sure the A units dim from about 40% to 100% so it sounds like just what i would expect.

240 at full blast can hit 260W, and then youre also measuring on the AC side and must include the 91-93% efficiency which eats up another 20W or so
So my COBs can be driven at 1.25A instead of 1.05A? Or is that what driver consumes?
Or in other words: if I set up COBs at 0.8A (reading at kill-a-watt meter), that means COBs are actually at 0.8A or not? Or let's say 1.2A, if driver is only 1.05A...
 

CobKits

Well-Known Member
the amperage on the AC side really has nothing to do with the amperage on the DC side

get a cheap multimeter and read the voltage and current on the DC side
 

pop22

Well-Known Member
I beg to differ with you on transplanting. I've made a study of it and have transplanted 100s of seedlings. I can transplant and see growth within hours of doing so. My transplant rarely miss a beat, no stalling or failing. The key is the right size starting pot and timing. one quart pots or containers ( I like cottage cheese containers, the rootball doesn't stick to it like plastic pots ). I transplant based on the width of the leaves. When the leaves are as wide as the container, transplant. Usually 7 to ten days. And contrary to another popular myth, it works well with autos also.

transplant? dont touch that thing for at least 4 weeks
 

CobKits

Well-Known Member
well having it semi rootbound kinda helps as the roots dont get all disturbed it pops out like a solid mass

i havent used soil in 20 years anyway ;)
 

jonsnow399

Well-Known Member
well having it semi rootbound kinda helps as the roots dont get all disturbed it pops out like a solid mass

i havent used soil in 20 years anyway ;)
If its rootbound, the roots in a cup are circling, unless you trim them they will continue to do that in a new container. You can trim them but it stalls the plant. If you use airpots you just take them apart with no root disruption or need to trim them.
 

CobKits

Well-Known Member
So you saying kill a watt meter is useless for adjusting lights?
not at all. in fact if you use the datasheet to estimate driver efficiency you can get a pretty good idea of cob wattage

And those wonderful MW drivers are consuming much more than they should without influence on COBs?
yes, at 110V input smaller drivers like the 240 are around 92%

so if your wattsup is pulling 280W, your cobs are getting 280*.92=258W. the other 22W is the heat coming off the driver

92% was jsut a guess you can look it up on datasheet (which is also only typical for one of the models on the datasheet which may or may not be yours, so an estimate)
 

CobKits

Well-Known Member
if you want to know actual current to each chip you have to measure it. because voltage will vary with whatever your heat solution is, a $10-20 multimeter should be in everybodys toolbox, can solve a lot of problems and save a lot of shocks
 

KonopCh

Well-Known Member
Driver is 93 or 94%. So 280 * 0.93 = 260W, still over spec for that driver. I really don't understand this... So my COBs actually get 260W with HLG-240H-C1050A driver?

Can the same math be used in amperage? 1.25A * 0.93 = 1.16A ? So my COBs getting 1.16A on 1.05A driver?

Thank you!
 
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CobKits

Well-Known Member
no! the amperage on te Dc side is independent because the voltage is completely different

the efficiency is already calculated

AC V x AC A x EFF= DC V x DC A

unless your driver is wired to 220V, it is not hitting 93%
upload_2017-7-14_7-33-42.png

per meanwell test report your driver should be pulling ~1.05-1.06A from the wall on the AC side and delivering ~1.28A to cobs when Io is cranked all the way up

upload_2017-7-14_7-36-51.png
 

CobKits

Well-Known Member
people spend a lot of extra money on cobs to squeak out a few extra percent when its all right there for next to free if they can take the time to run a 220V circuit to the grow room
 

KonopCh

Well-Known Member
Driver is 93 or 94%. So 280 * 0.93 = 260W, still over spec for that driver. I really don't understand this... So my COBs actually get 260W with HLG-240H-C1050A driver?

Can the same math be used in amperage? 1.25A * 0.93 = 1.16A ? So my COBs getting 1.16A on 1.05A driver?

Thank you!
So I can use watts to see how much light I getting, if I understand you?
And if I want amperage I must buy multimeter.
But if by calculations I get 260W (above quote), then obviously amperage is higher than 1.05A on DC side. Up to 1.25 or 1.28A as you said.
 

pop22

Well-Known Member
**** I error-ed here,wrong voltage...and figured out what I'll use***


I think you missed my reply. You asked me about the voltage of the strips @ watts consumed.

they are:

22.7V @ 1000ma and 23.3 @ 1400ma. I want to run 8 strips
 
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