Clamping it to a damp rag migh be enough to prevent parts from coming off the backside since you are heating the biggest component on the board.
I have this in the mail: Cree XHP70 M4 40H 4000K Neutral White LED - 1 Piece plus a āNichia 219Bā.
Aiming for 4ā2/4ā8A of output.
The 219B is for a 3-mode SK68 clone mod.
Cheers :partying_face:
Barkuti,
How do know if your inductor is the right sized prior to installation? Do you test it or make an educated assumption? Do the ferrite cores vary in composition or can you wrap any ferrite core? I save all of the bits and pieces of everything I tear apart. I could easily re-wind an inductor but have no clue on the theory side of things.
PS, Nice necro post.
Well, I'll probably make an inductor out of an old school AC/DC brickwalwart's transformer secondary windings. I have a 230VAC/9VDC transformer (edited: this one is a keeper, using it to power up the kitchen scale you can see some messages below), a multi-DC output 220VAC/(12/9/6)VAC transformer too, and a rare and chunky 230V/35V unit. I'm gonna put a 9V cell in my used kitchen scale to see how much it wheighs. ;)
Cheers ^:)
P.S.: fixes and updates here & there (2016/05/0, 07:17).
Ooops!
With respect to the size, my plan is to make it at least big enough to output 4ā8A of current without much effort so, if make it a bit smaller than this threadās example replacement, it should handle 5+A well.
Cheers :partying_face:
P.S.: I should not afford more than 10mm driver board height, or else Iāll have to chop a bit the baseplateās internal pill support heatsink, LOL!
An image is at least worth a thousand words.
Cheers :partying_face:
P.S.: If I put a can of Fanta Zero Naranja (Orange) on it, I can read 343g and 12ā oz, respectively. :innocent:
I got news for you, itās not gonna fit under a 10mm ceiling.
I got news for you, itās not gonna fit under a 10mm ceiling.
Itās my tuned multi-toolās time ! LOL!
Cheers :partying_face:
Some of those transformer Cores are just held together with spot welds. Hit it one good hard whack at the seams with a cold chisel and it will pop right open and then you can pull the windings right out. If you were just wanting to salvage the wire thatās how I would do it.
Well, I was just editing my #26 post above, but realized it was such an overhaul I'd better post something new, LOL!
The brickwalwart, a linear PSU, remains āwholeā.
The small one, as said above, is a 220/(12/9/6)VAC transformer.
The big-ass lady is a (220/115)/35VAC transformer of unknown amperage; I bet it does 2A output for sure, I once tinkered with a smaller 24VAC 2A unit and it happily campered at 3+A so, 3A sounds nice.
What is more, since the official mains voltage is now 230VAC (where I live I get 240-250VAC hehehe), if I connect mains into the 115VAC primary winding, the output will be 70+VAC RMS (100+V peak). Thinking in building me up a nice CC/CV buck power supply. 8^)
Cheers ^:)
Iāve taken a look at the windings of the small AC transformer, seems to be AWG24 solid copper wire. I think I can make a coil small enough to fit in the limited space I have (āā 18ā75mm pill internal diameter) and be good to perform well for a couple extra amps (up to 5). Figures:
Sounds good enough?
Cheers :partying_face:
P.S.1: about 650mm (25ā59ā) of wire lenght leads included, for a total of 56ā264mĪ© coil resistance.
P.S.2: not nice, too much resistance. I may roll 2-3 coils in parallel, reducing diameter a bit, less inductante but higher current handling; over-analizingā¦ :person_facepalming:
Hello!
I've found the review of this driver at lygte-info.dk: Review/Test of XM-L Multi-cell Circuit Board, 3A, 5.5-12.6V
In the review, HKJ (?) complains about the fact that the driver (supposedly a 3A unit) pumps out too much current to the led and, after a quick gaze at the upper right photograph of the review, the evidence is clear: he received a pre-modified driver, a 0'33Ī© resistor can be clearly seen stacked over two of the regular R200s onboard (there's a third one by the other side). As the CC reference voltage is 0'2V, applying Ohm's Law: I = 0'2V / 0'33Ī© ā 0'61A; this precisely matches his measurements: 3'6+A of driving current.
Good to see it is quite efficient for driving 2S emitters.
Cheers ^:)
Iāve taken a look at the windings of the small AC transformer, seems to be AWG24 solid copper wire. I think I can make a coil small enough to fit in the limited space I have (āā 18ā75mm pill internal diameter) and be good to perform well for a couple extra amps (up to 5). Figures:
Sounds good enough?Cheers :partying_face:
P.S.1: about 650mm (25ā59ā) of wire lenght leads included, for a total of 56ā264mĪ© coil resistance.
P.S.2: not nice, too much resistance. I may roll 2-3 coils in parallel, reducing diameter a bit, less inductante but higher current handling; over-analizingā¦ :person_facepalming:
Hi Barkuti,
This page answered my question. I thought maybe you were just roughly ballparking it but I see now you are using a calculator.
I see the HAM guys concern themselves with core recipes and frequenceis. Is this not an issue with LED drivers?
What will you use for a core?
Forgive my ignorance, Iām not an EE.
A more adequate design with two stacked coils in parallel, with about 461'61nH and slightly below 25mĪ©, which I find it'd required for 5+A of current handling. Air core.
No problems with RF noise in toroidal inductors: a virtue of their geometry.
So far, this is what I've come up with. I'm no literate in these matters, though.
Cheers ^:)
The 6A is a current limit but doesnāt tell you the resistance does it?
The 6A is a current limit but doesnāt tell you the resistance does it?
Of course it doesn't, yet it looks ā to the inductor the OP used, size wise. If I deem it to be too chunky, since that ought to be built around some ferrite core, I can always unroll a chunk of it: half of the wire should still provide Ā¼th of the inductance (seems to provide plenty) with just Ā½ of impedance. A third of the roll would still provide ā9Ī¼H at ā of impedance.
I do know Jacksheesh about inductors, mind you.
Cheers ^:)
P.S.: the inductors in the test photos look to have approx Ā½ of the winding lenght with respect to the pair I've bought so, my pliers will talk; of course there's still plenty of time for someone to chime in with more enlightening informationā¦
Heck!
No need to chop off anything! I've ordered a couple of inductors so, I'll dismantle one and then re-roll its wire carefully around the other's winding!
It's gonna be a massive amount of copper wire coil attached to the board soā¦ free heatsink!
Sounds that good?
Cheers ^:)
Original date of post: 05/05/2016.
Edited for make-up of broken unimportant image links.
Ended up cancelling those inductors, just thought that was not the way to go.
These are the inductors which seem to be like the one the OP used: 10Pcs 33UH 3A Toroidal Wound Inductor Nude Inductance Magnetic Inductance
Wire lenght/section wise, that is nearly 32mĪ© about 64mĪ© of resistance which, at 5A, would dissipate ā1'6W of power.
DIY alternative: 5pcs Micrometals Amidon T50-6 Iron Powder Toroidal Core Iron CoreRF Toroid HF HAM QRP Inside Diameter 0.7cm Outer Diameter 1.2cm
Stopping this over-analyzing galoreā¦
Cheers ^:)
Original date of post: 05/05/2016, or soon thereafter.
Edited for make-up of broken unimportant image links.
T50-6 core specifications at Amidon corp.
These are the inductor cores I've bought. Because of the relatively high output current and me deliberately wanting to keep efficiency as high as it could reasonably be, I've gathered some more info as to confirm my theory of increasing current handling through winding in-parallel magnet wire and:
Choosing the type of wire @ info.ee.surrey.ac.uk
Well, what is said there confirms my theories. I'll be able to wind up 30 turns of twin in-parallel AWG24 magnet wires for about 3'2Ī¼H of inductance with half of the resistance compared to single AWG24 winding.
Cool!
Cheers ^:)
Original date of post: 05/05/2016, or soon thereafter.
Edited for make-up of broken unimportant image links.