MeanWell LED Drivers: 3 in 1 Dimming Function.

Rahz

Well-Known Member
Hi everyone,just making things clear. Two Elg-100-1050 to one 100k dimmer pot is ok?
It will work, you just won't get any dimming until you've turned the knob half way. 100K ohm / # of drivers, so 50K ohm for 2 drivers to get full range, or maybe 55-60K ohm to insure you're hitting 100% brightness when open.
 

dionysus4

Well-Known Member
There are two main types of pots :
Linear and Logarithmic.

http://www.beavisaudio.com/techpages/Pots/
http://sound.westhost.com/pots.htm

Linear type pots are the ones of interest .
Dimming with them , is smooth and ,of course, LINEAR.

Low cost Pots usually have an action of a (almost) single turn
( 0 to max resistance value )
and can dissipate about 1/4 of W ,
meaning 250mW .

( A single low -cost pot can control up to ...~ 50 drivers ,
before it's resistive material heats up and fries ...)

View attachment 3211254


As we said ,shorting Dim- and Dim+ ,ain't such a great idea....
So a "Low Limiter' resistance must be set in series with the Pot .

In case of a single driver ,that Low Limiter should be 10K (Io= 10% of Io_max ) .

So If wiper goes to A ( 0 Ω ) , minimum resistance will be 10K .

*Low limiter can be placed in series after wiper ,also.

**If A and Wiper are used then action should be ,leds go brighter when pot's knob is
turned clock-wise ,and dim down with anti-clockwise motion.

If B and wiper are used then turning Pot's knob clockwise will dim the leds down ,
whilethe anti-clockwise rotation will increase driving Io up to max.

In case of multiple drivers :

Number of drivers ____Pot value___Dis.Power.______LowLimiter Value10%____
2 50KΩ 10mW 5K
3 47KΩ 15mW 3.6 K
4 25ΚΩ 20mW 2.5K
5 20KΩ 25mW 2K
6 20KΩ 30mW 1.6K


so in case of using the 2ok pot with 6 drivers does this mean that the lowest dim value will not be off?
like if i use a 50k for 3 drivers? what dif does that make?
 

stardustsailor

Well-Known Member
6 pairs of Dim wires connected in parallel ..
20K ( linear ) pot ...

100/6 =16,666 k
That means the max output will not be at the far end of the pot ,
but a tad before that ...

At the other end of the pot (min value ) you will get 0K resistance ,
but that does not mean actual "LEDs off " ( Although the LEDs/COBs will go completely dark ) ..
It's just the drivers on protection mode .
The drivers should not go lower than 10% of their max output ...
Thus ..16,666K / 10 = 1,66 K ...

A resistor set of 1,66 K shoul be connected in series with the "start"( min Io ) or the " wiper " .
to ensure that the minimum value of the pot is 1,66 K and not 0 K .
( the max in that case is 21,66 K _ ideally .. )
Thus the dimming range of the drivers is : from 10% (min Io = 0.1* Io max ) to 100% = Io max

( from 100mA to 1 A ,
from 140mA to 1400 mA
from 200mA to 2A
and so on ... )
 
Last edited:

dionysus4

Well-Known Member
6 pairs of Dim wires connected in parallel ..
20K ( linear ) pot ...

100/6 =16,666 k
That means the max output will not be at the far end of the pot ,
but a tad before that ...

At the other end of the pot (min value ) you will get 0K resistance ,
but that does not mean actual "LEDs off " ( Although the LEDs/COBs will go completely dark ) ..
It's just the drivers on protection mode .
The drivers should not go lower than 10% of their max output ...
Thus ..16,666K / 10 = 1,66 K ...

A resistor set of 1,66 K shoul be connected in series with the "start"( min Io ) or the " wiper " .
to ensure that the minimum value of the pot is 1,66 K and not 0 K .
( the max in that case is 21,66 K _ ideally .. )
Thus the dimming range of the drivers is : from 10% (min Io = 0.1* Io max ) to 100% = Io max

( from 100mA to 1 A ,
from 140mA to 1400 mA
from 200mA to 2A
and so on ... )

you da man!
 

stardustsailor

Well-Known Member
6x 3in1.JPG

TP1 to TP6 : Dim + #1 to Dim+ #6 wires
TP7 to TP12 : Dim - #1 to Dim- #6 wires .
Far counter clock wise = min setting ( pot = 1,66 K ) =output 10% of max .

Far clock wise =( over range ) max setting (pot = 21,66 K )
Actual max output, may be ~ 110-115 % of the rated max output )
Fror example ,HLP drivers rated at 1400mA max ,the actual max output is about 1650-1660 mA ..
 

dionysus4

Well-Known Member
View attachment 3583422

TP1 to TP6 : Dim + #1 to Dim+ #6 wires
TP7 to TP12 : Dim - #1 to Dim- #6 wires .
Far counter clock wise = min setting ( pot = 1,66 K ) =output 10% of max .

Far clock wise =( over range ) max setting (pot = 21,66 K )
Actual max output, may be ~ 110-115 % of the rated max output )
Fror example ,HLP drivers rated at 1400mA max ,the actual max output is about 1650-1660 mA ..

sorry i dont really understand all that

i will now just connect 1 ELG 150c to a pot
so i need a 100k pot and resistor 10k?
 

dionysus4

Well-Known Member
ok did a bunch more reading and i think i got it for resistance dimming


BUT i found some interesting looking drivers in china that can run a cxb3590 up to 1700mA
the catch is they only have 0-10v dimming
can i connect a 10v power suply in parallel to dim and also run fans?
 

robincnn

Well-Known Member
BUT i found some interesting looking drivers in china that can run a cxb3590 up to 1700mA
the catch is they only have 0-10v dimming
can i connect a 10v power suply in parallel to dim and also run fans?
You can use 10V power supply. I have seen some on ebay. Fans should run fine at 10V
You can also use 12v power supply and step it down to 10V using a LM7810 voltage regulator.

To achieve dimming you can do a 2 resistor to create variable 0-10V
upload_2015-11-20_17-58-45.png
See implementation 2. Their V aux is just like 12V
They use 1kohm resistor and 5k ohm pot to get variable voltage across dim + and dim -
You can actually use 12V and no need for 7810. Just with correct resistors you can get 0-10V
Calculate like this
Current = voltage/ resis
=12 V / (1K+5K) = 0.002A
Then 5k × 0.002a = 10V:weed:

Now reduce pot to 1k ohm by turning it down
12 V / (1K+1K) = 0.006A
Then 1k × 0.006a = 6V:weed:
See same happened in implementation 2
It says 1k ohm 60%
So you can do dimming but it is not linear.
If you have external 12V I would put 12V + on that 1k resistor and - on the dim -.
 
Last edited:

dionysus4

Well-Known Member
You can use 10V power supply. I have seen some on ebay. Fans should run fine at 10V
You can also use 12v power supply and step it down to 10V using a LM7810 voltage regulator.

To achieve dimming you can do a 2 resistor to create variable 0-10V
View attachment 3587782
See implementation 2. Their V aux is just like 12V
They use 1kohm resistor and 5k ohm pot to get variable voltage across dim + and dim -
You can actually use 12V and no need for 7810. Just with correct resistors you can get 0-10V
Calculate like this
Current = voltage/ resis
=12 V / (1K+5K) = 0.002A
Then 5k × 0.002a = 10V:weed:

Now reduce pot to 1k ohm by turning it down
12 V / (1K+1K) = 0.006A
Then 1k × 0.006a = 6V:weed:
See same happened in implementation 2
It says 1k ohm 60%
So you can do dimming but it is not linear.
If you have external 12V I would put 12V + on that 1k resistor and - on the dim -.

thanks so much for your reply, if only i understood it lol

here is what im thinking

Screen shot 2016-01-17 at 19.13.35 PM.png
 

dionysus4

Well-Known Member
This looks good too. Should give a linear dimming with a linear pot.
Looks like this way you can use any value of potentiometer. Like 25k , 33k, 50k ohm or 100k ohm pot

cool tnx

really any value? huh....?

but i will be dimming the voltage with resistance from the pot not dimming the power supply
 

Fastslappy

Well-Known Member
both ,
if u leave the leads open (capped off ) then the drivers runs @ full cap & that can be approx 106+ 0r - %
with a dimmer it will only go to 100%
and you can add a switch to the circuit & get the best of both worlds
 

PyspherE

Well-Known Member
Hey RIU!

Im putting together a light system for my 4x8 tent. Ive decided on 28x CXB3590 36v 3500k powered by 7x Meanwell HLG-185H-1400b and mounted on 7x HeatsinkUSA 5.886" profile x 44". Im pretty sure I have the dimming down but just want to confirm im doing things right.

With 7x drivers on a single pot i need a resistance of:
100kohms/7drivers=14.29kohms

My thinking is to use a 5k resistor in series with a 10k pot for a total resistance of 15Kohm.

This will leave a small portion of the dial unusable but its miniscule and should allow me to dim down to about 34%

Can anyone confirm if im on the right track?

Be Safe! Much Love!
PyspherE
 

JavaCo

Well-Known Member
Hey RIU!

Im putting together a light system for my 4x8 tent. Ive decided on 28x CXB3590 36v 3500k powered by 7x Meanwell HLG-185H-1400b and mounted on 7x HeatsinkUSA 5.886" profile x 44". Im pretty sure I have the dimming down but just want to confirm im doing things right.

With 7x drivers on a single pot i need a resistance of:
100kohms/7drivers=14.29kohms

My thinking is to use a 5k resistor in series with a 10k pot for a total resistance of 15Kohm.

This will leave a small portion of the dial unusable but its miniscule and should allow me to dim down to about 34%

Can anyone confirm if im on the right track?

Be Safe! Much Love!
PyspherE
Math looks correct to me, You really don't want to dim much lower than 33% anyways, efficiency goes to hell
 

nevergoodenuf

Well-Known Member
Don't forget to add a kill switch to the dimmer. This will give about an 8+% boost in output. Get a watt meter so you can confirm the output. Also the cheaper the pot, the less accurate the pot. I use the watt meter to put 50 watt incruments on the dial. They will not be evenly space.
 

BobCajun

Well-Known Member
There are two main types of pots :
Linear and Logarithmic.

http://www.beavisaudio.com/techpages/Pots/
http://sound.westhost.com/pots.htm

Linear type pots are the ones of interest .
Dimming with them , is smooth and ,of course, LINEAR.

Low cost Pots usually have an action of a (almost) single turn
( 0 to max resistance value )
and can dissipate about 1/4 of W ,
meaning 250mW .

( A single low -cost pot can control up to ...~ 50 drivers ,
before it's resistive material heats up and fries ...)

View attachment 3211254


As we said ,shorting Dim- and Dim+ ,ain't such a great idea....
So a "Low Limiter' resistance must be set in series with the Pot .

In case of a single driver ,that Low Limiter should be 10K (Io= 10% of Io_max ) .

So If wiper goes to A ( 0 Ω ) , minimum resistance will be 10K .

*Low limiter can be placed in series after wiper ,also.

**If A and Wiper are used then action should be ,leds go brighter when pot's knob is
turned clock-wise ,and dim down with anti-clockwise motion.

If B and wiper are used then turning Pot's knob clockwise will dim the leds down ,
whilethe anti-clockwise rotation will increase driving Io up to max.

In case of multiple drivers :

Number of drivers ____Pot value___Dis.Power.______LowLimiter Value10%____
2 50KΩ 10mW 5K
3 47KΩ 15mW 3.6 K
4 25ΚΩ 20mW 2.5K
5 20KΩ 25mW 2K
6 20KΩ 30mW 1.6K
What makes you think shorting the dim leads on a driver with 3 in 1 dimming is bad for the driver? In data sheets it says less than 1v OR SHORT results in minimal brightness. Nowhere in anything have I ever seen something like "do not short the dim leads, will cause driver damage". I had an Arduino wired to a couple drivers and it was shorting and leaving open the dim leads at many times per second. Thing should be toast by now, by your reasoning.
 
Top