DIY LEDs - The write-up

[007Bond]

Thank You! Let me rattle that around upstairs a bit.

 

[kcress]

Answers to some higher-up-the-page questions:

kcress, I am curious so could you explain more? Is the harmonics due to a lack of PFC? Also curious 6 per circuit or per fuse box?

Thanks

I'll quote myself here:

To answer your PFC question. The Meanwell 60-48D has just diodes on the front-end that charge a capacitor. Capacitors store energy with voltage. What happens is the capacitors charge up to some level and operation begins. Every power line cycle which varies from 170V to -170V can only add power back to the capacitor, (that is continuously drained by running the LEDs), when the absolute value of the voltage exceeds whatever the drained down voltage of the capacitor is at that moment.

This means the power can only be gotten from the outlet in tiny sporadic gulps. Those gulps are large sudden current spikes because all the energy needed by the system has to come in those tiny gulps.

Those gulps can be 10A even though the name plate states 1A or 0.5A. That's because the name plate shows the average current. When you stack up a pile of these things you may have 300A pulses being drawn from your outlet even though the average current is only 10A.

The heating in your breakers and wiring and outlets is only a function of I-squared R. Which means the heating is very sensitive to the current I. Your wiring is set up for "average" current not these repetitive pulses.

In most cases you won't have a problem - you'll get away with it. Your wiring will be running hotter than predicted by the average current values listed on the Meanwells. If you have no weaknesses (today) like a bad connection in your house wiring you probably won't have an issue.

As for the startup problem with the inrush the inrush listed only occurs when you power-on the MW and the power line voltage which cycles, as stated above, is at the maximum values. Any other time it's less. This means you are rolling the dice every time you energize the MWs. You may turn them ON and the first time the breaker trips. Or the 300th time the breaker blows as it all depends on where in the power line cycle the switch gets thrown.

If you always leave the MWs ON but just dim them then your breaker tripping opportunities are obviously reduced.

The aforementioned problems that diode-front-end power supplies cause is so onerous to the power companies and to places where a lot of switching supplies are used, like offices with a bunch of personal computers, that the laws are changing on the subject of switching supply front ends.

Enter the Power Factor Controlled (PFC) front ends. Instead of diodes hooked to capacitors the diodes are replaced with a controlled network of transistors and inductors. The control directs the current drawn from the power source to be drawn smoothly over the entire power line cycle not just in gulps - no gulping allowed. This avoids ALL the current pulsing and wire heating. This same network can provide the bonus of eliminating the inrush too. As the initial energy drawn on start-up can be actively limited.(Note that these PFC Meanwells don't limit inrush much.)

The HLG line is Meanwell's PFC or "active front end" current drivers. They would be the choice for those wanting a "bunch" of drivers.

007Bond; It means you switch to something bigger. You have a 5 tons of rock to move? You have to switch up from that Volkswagon. The HLGs as Fishman suggests is the way to go. Or the DIY drivers in the other thread.

 

[TheFishMan65]

Thanks kcress, was that in this thread? I don't remember reading it.

 

[bamf25]

Ok, you mention rolling the dice with the meanwells? Has anyone here had this problem. If so what were the conditions?

 

[kcress]

If you leave your MWs energized the opportunity for a tripped breaker is greatly diminished.

 

[brassmonkyballs]

If you leave your MWs energized the opportunity for a tripped breaker is greatly diminished.

To be clear you're only referring to the ELN series correct?

 

[TheFishMan65]

Yes, but it is probably true for anything that has an inrush. So based on this

(Note that these PFC {HLG] Meanwells don't limit inrush much.)

from kcress it applies to the HLG also.

 

[bamf25]

Great, I undestand the idea of inrush, but has anyone see it happen?

 

[007Bond]

FishMan, Thanks for your input! Education is a good thing. Your saying you are comfortable figuring the ERNs at 1.3A, 100% instead of 80% ,so if you take the 1.3 divided by say 1000ma. running current, would get 1.3 strings of 12 to 14 leds? am I figuring this correct? or if run in parallel you would have a total of 2.6 strings or 36.4 leds @ ELN? Yes. I think I would prefer the multi ERNs over single HLGs to have multi control over start up times.

 

[TheFishMan65]

Well you can not have fractional strings. String theory forbids that, oh wait wrong subject . So you can have 1, 2, 3, or 4 strings. Beyond that the currents IMO are too low.

Multiple ELN are fine unless they cause problems in the house. In which case you have to spend more the the HLG. IMHO just start with the HLDs.

 

[kcress]

HLGs could give the same tripping problem except why would you ever have more than one or two of them?

Great, I undestand the idea of inrush, but has anyone see it happen?

bamf25; Yes, I see it all the time. Using the switch on the back of the power supply not the button on the computer case, turn your desktop comp off. Wait ten minutes. Turn on an incandescent light nearby. Look at it as you turn on the switch for the power supply. You'll see the incandescent light dip briefly. That's the inrush.

The current is so large that it's actually limited by the house wiring and the power cord itself. If the the house wiring is long enough the inrush is reduced in magnitude but increased in duration. It all depends on this and the circuit breaker model, age, temperature, loading, and most importantly the exact point on the power line cycle the switch is flipped, on whether or not the breaker will trip. (a crapshoot)

 

[brassmonkyballs]

FYI....today I put 28 XPE RB on an ELN 60-48P. Can get 850ma out of them for each string but dialed back to 700...they are within 60ma of each other but didn't swap out any. Voltage on each string is 44.1V and 44.2V. So well within the 48V and fixture and driver are running about 100 degrees F.

As for the discussion of in rush...just put the dimmer power on the timer and leave the driver powered up and the in rush problem goes away....power off the LEDs via the dimmer.

 

[vthondaboi]

It looks brighter than that but the color of the corals are true. Tank is a 72x30x28 roughly 250G.

48 XPE RB @ 700ma and 24 XPG CW @ 1050ma. No lenses. PAR at the top of the middle rock is 300 and the front sandbed is 100.

I just turned on some 6 month old Phoenix 250DE on Icecap Ballasts with PFO reflectors. The glass from the reflectors were approximately 8" from the top of the tank. Par at the same spots were 275 and 115. 275 was a max and it varied down to 250 if it didn't hit a hotspot.

I plan to add optics to LEDs on the edge of the fixture. With that done I'm confident that I won't need to add more LEDs until a couple years to make up for age.

 

[007Bond]

It looks brighter than that but the color of the corals are true. Tank is a 72x30x28 roughly 250G.

48 XPE RB @ 700ma and 24 XPG CW @ 1050ma. No lenses. PAR at the top of the middle rock is 300 and the front sandbed is 100.

I just turned on some 6 month old Phoenix 250DE on Icecap Ballasts with PFO reflectors. The glass from the reflectors were approximately 8" from the top of the tank. Par at the same spots were 275 and 115. 275 was a max and it varied down to 250 if it didn't hit a hotspot.

I plan to add optics to LEDs on the edge of the fixture. With that done I'm confident that I won't need to add more LEDs until a couple years to make up for age.

Did you use ELN power? if so how many? What is your led spacing, and # of rolls, their length and their spacing between them? Thanks

 

[kcress]

Thanks for the report Brass.

vthondaboi; Thanks for the picture.

 

[perikaruppan]

Are these reading correct? ..

1.
Made a 8 in 1 CAT 4101 Design and it has been working brilliantly on my Edision LEDs.
used the same PCB for the newly purchased XPGs (CW/NW) and XPE (RBs) and used only 4 CATs to drive 24 LEDs, but came across this problem:
@ the power supply the voltage is 22.6V, at the input of the CAT Board it is 20.2V and the output of the CAT is 19.2V(about 3.2V per LED, got 6 on them) and 19.7V(got 3 XPGs and 3 XPEs on this)....and current is constant at 700mA...

To attain this, i slowly increased the Voltage from 20V(thats the min) from the Input Power Supply so that i reach exactly 700mA and then measured all the above parameters...

is the above reading correct? will there be so much voltage drop across the input power supply and input voltage to the CAT? its just a wire that is between the input power supply and the CAT PCB...

2.
Initially when i just just drive 1 LED the input voltage is not that high, it is only 21.6V and the current is 700mA, but when i start getting the 2nd string in place, the Amps drop to 0.63, then to 0.56A when all 4 are connected, @ this juncture the CAT is perfectly cool as cucumber... but when i crank up the input voltage to about 22.6V to get the 700mA as the current, the CAT is slightly warm... but when i use another board with different resistors to drive at 1A, the CAT gets kinnda hot ...
Is this common for the current to drop when more strings are attached?

the LED strings attached to the board are in this sequence...
1. First 6 XPG CWs - 700mA
2. Second, 5 XPGCW and 1XPGNW, 0.64mA
3. Third, 6 XPG CWs - 0.59 ma
4. Finnally, 5 XPERB's and 1 XPGCW , 0.56mA

Always the current was measured across the 1st string only...

 

[007Bond]

mr.wilson
Registered Member



Join Date: Dec 2005
Location: Toronto, Canada
Posts: 2,090
Quote:
Originally Posted by chingchai
Shawn. Thanks.
The one that use in Peter's tank. Right?
yes, we are getting 350 PAR at 30" water depth. We will be getting some 100 watt single light source LED this week from Orphek to try out. I will test PAR in our 6' deep reservoirs and let you know. They are also working on a 300 watt single chip.

From the DSPS Tank from Thailand (1000 gallon+ ) thread.

 

[TheFishMan65]

vthondaboi, I would not add anything right away and watch for bleaching. I had 300 PAR on ths surface and every SPS (about 8 inches) bleached. wait and see and don't be afraid to turn them down IMHO

perikaruppan - wrong thread, but you figured that out I posted in the correct one

007Bond - great guy but I don't get the post

 

[007Bond]

Just thought it interesting, Mr. Wilson hitting 350 PAR at 30", and using 100w single chip leds.Looking into 300w leds. Some serious power!

 

[TheFishMan65]

Missed that I soon as I got to post counts I went Huh? Do you have a link?