Meanwell LDD -1000hw & variable resistor

[ma3com]

I just want to ask if I can use variable resistor to make the dimming in use Meanwell LDD -1000hw without using controller or I must have controller like arduino .

 

[Pny]

You need a PWM signal for dimming the Meanwell LDD's.

 

[ma3com]

I try to use variable resistor with meanwell LDD and it is work but I don't know if I will have problem after days

 

[oreo57]

I try to use variable resistor with meanwell LDD and it is work but I don't know if I will have problem after days

not seeing how this is possible..How exactly are you wiring the pot to it PWM circuit only has one "feed" wire.. And the only other wires are either V in from PS or V out to LED..

spec sheet lists "H" as >2.5 to approx. 6V or low (off) <.8V or short..

http://www.meanwell.com/search/LDD-H/LDD-H-spec.pdf

So there is th possibility that PWM is just "sveraged" to produce an analog signal inside, meaning Pot dimming (w/ a power source ) is possible????

I'm confused..

 

[d0ughb0y]

I try to use variable resistor with meanwell LDD and it is work but I don't know if I will have problem after days

If it is truly pwm only, then your test would not work. Does it actually dim when you turn the variable resistor? or is it just On or Off once the variable resistor crosses a certain value?

If it is just on/off when you turn the resistor and not dimming, then yes, you need pwm.

After reading the specs again, as post above say, if DIM pin voltage is > 2.5, the LED light is on. If DIM pin voltage is < 0.8, then the LED light is off.

 

[mcgyvr]

I did not see anything in the meanwell ldd specs that says it must be pwm only.

I don't see that it can't be used as a rocketship either in the datasheet...:spin2:

PWM is clearly stated and as such it should be dimmed with PWM. (100Hz -1KHz) Driving it from a constant voltage source is below the recommended frequency and should not be done.

Just use a 555 timer/pot to create the PWM signal if you are too cheap to do it correctly.. No "controller" needed.

 

[mcgyvr]

I don't have one but these seem to achieve dimming by turning the output on/off in relation to the PWM signal.. Not by adjusting its output current.

 

[d0ughb0y]

if the device uses an analog voltage for control, then using pwm or variable resistor will work (jebao pumps for example are in this category). but if the device uses pwm signal to turn itself on and off, then only pwm will work. It looks like the ldd driver is the latter.

you can get an arduino pro mini for $2.25 (but you need an FTDI cable), or an arduino nano for $4.95 or an UNO for $7. The arduino pwm frequency is within the specs of the ldd driver.

 

[Pny]

I don't have one but these seem to achieve dimming by turning the output on/off in relation to the PWM signal.. Not by adjusting its output current.

Most circuits do it this way, and you get less color shift by doing it like that.