Led driver potentiometer

George2324

Well-Known Member
i need to provide a min resistance of 630 ohms and a max resistance of 3125 ohms to my drivers

I've got the 630 ohms covered by a fixed 630 ohm resistor however is there a way to put resistors in parallel or something to create the max resistance of 3125 ohm with a 5k potentiometer?

I only have a 5k ohm pot a 100k pot and 100 of the 630 ohm resistors.

It would be ideal if I can somehow achieve this by putting stuff in parallel etc ?

Is this possible?

Thanks
 

George2324

Well-Known Member
Does anyone mind checking my math to make sure what I think will work - will actually work?



A 630 ohm resistor in series to ensure all resistance is always atleast 630

And then 14x 630 ohm resistors in series to create 8820 ohm and 5000 ohm is parallel should make near 3200 ohm when pot is on max?
 

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George2324

Well-Known Member
It's the meanwell hlg-600h-36b

100kohm/n

I have 16 drivers so 100kohm/16 for 100% power

Which is 6250 ohm for 100% but I don't want to run them at 100% I want my max to be 50% so I need my resistor circuit to max out at the 3125 ohm and min 10% 630 ohm.

When i bought the drivers I might of accidently went too high on the wattage and if I run them at 100% I'll have 115w per sq foot
 

Airwalker16

Well-Known Member
It's the meanwell hlg-600h-36b

100kohm/n

I have 16 drivers so 100kohm/16 for 100% power

Which is 6250 ohm for 100% but I don't want to run them at 100% I want my max to be 50% so I need my resistor circuit to max out at the 3125 ohm and min 10% 630 ohm.

When i bought the drivers I might of accidently went too high on the wattage and if I run them at 100% I'll have 115w per sq foot
Sounds like a WIN to me at 30" from canopy. You'll fucking CRUSH IT.
 

George2324

Well-Known Member
Not to mention I now realise that 115w will produce 115w of heat so I'd need like 50,000 btu of AC to cool everything

I think my resistor circuit adds up correctly
 

nfhiggs

Well-Known Member
I made an error I didn't include the original 630 ohm resistor in the calculation.

Can anyone confirm if this is right?

Providing min 630 ohms max 3200(ish) ohms?

Thanks
Yes, your equivalent resistance calculation is correct.
 

CobKits

Well-Known Member
if youre never going to run above 50% why dont you shelve half your drivers and double up the number of cobs per driver?
 

George2324

Well-Known Member
Rather than start a new thread it turns out one of my drivers is outputting 0v on the DC side.. any ideas what's could be causing it?

Don't know if china will replace a faulty driver..
 

George2324

Well-Known Member
yes as long as you keep + to + and - to - it will work
Alright thanks i might do that anyway .. I'll have to recalculate resistance values for 100% with 8 drivers...

Dunno if I can do that With the resistors I have

Yeah don't think I can just ordered a 10k pot to use.
 
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