Setting to 0v

[ReefEnabler]

Hello!

I am going to attempt to Dim a set of BuckPuck LED drivers using the 1-10v interface. I need to set the voltage range to 0 - 5v using the profilux software.


Now the buckpucks are inverted. When fed a 0v signal, they will be at 100% brightness, and a 5v signal means 0% brightness. So if it only goes down to 1v, I lose 140ma (out of 700ma max)


So I need to know, will the 1-10v interface go all the way to 0 if set to in the software? And if so, will there be a smooth transition between 0-1v?

Thanks to anybody who can help.

Ryan

[ReefEnabler]

... ok well I went ahead and cut into a VSL extender cable and tested the voltage of the dimming 1 channel (brown) against ground (red).

By setting the L5 port to be 0 - 6v (the lowest available max), and then using 0-85% in the illumination period, I was able to generate a 0.08 - 4.96v signal, very close to the 0-5v the buckpuck needs. Dimming is fairly smooth, but when its climbing up from 0 to 2.4v, suddenly it drops back down to 1.3 or so, and does the same thing in the 3v area.... other than that it works.


I just tested it on a single buckpuck (connect brown to buckpuck CTRL wire and red to LED (-) wire and it works. In practical application, the LEDs shut off once illumination gets to 70%, which is probably around 4v (remember buckpucks are backwards, so 0% is MAX, and 70% is the true MIN before shutoff)

The LEDs are extremely dim at this point, but unfortunatetly you still notice them come on or off. I was hoping it would be so smooth you don't notice the ON... maybe achievable with some extra circuitry?

[Matthias]

the output signal of our 1-10V interface is stable in every position, if it drops somewhere there must be something wrong with the connected items - or you enabled the cloud simulation

I think you need a circuit which converts 1V...10V into 4V...0V and 0V to 5V (for shutting off) or this circuit uses additionally the on/off signal (relay output)

[ReefEnabler]

When I tested voltage, I was not using any device hooked up. Just connecting the Brown and Red wires to my multimeter with aligator clips and watching the voltage readout over a 5 minute dimming period. The drops only last 2-3 seconds and the voltage stabilizes. They always happened around the same place.

Do not have cloud or moon simulation enabled.

I am testing this at the end of a 25meter VSL extender, could that have something to do with it?

[ReefEnabler]

Matthias,

can you please verify for me the maximum current rating of the Dimming CTRL wires?? Somebody guessed around 10ma but would be good to know for sure.

I'm trying to figure how many pucks I can run per channel. The datasheet says their control wire is "less than 5ma" but isn't too specific.

I wonder what will happen if I try and wire too many to a single 0-5v signal.... will it just have trouble getting up to 5v?? Or is my current basically doubled since I'm only going to 5v not 10v?

[Matthias]

I don't understand why the voltage should drop - this is not usual, otherwise we had many complaints about not smooth dimming in some ranges

10mA is the maximum, if the load is too high possibly the 0V or 10V can't be reached (this depends on the input circuit of the LED-driver)

[ReefEnabler]

I will test this more later. I will also test with the VSL cable plugged directly into an L-port on the profilux, instead of at the end of a few other extension cables.

I have a suspicion that the voltage drop only happens when ramping from 0-5 so quickly (5 mins) and that it won't really happen with a much longer period.

So I guess the only way to really know what will happen will be to wire up 6 pucks and measure the voltage and see if I can still hit 0.08 and 4.96 volts with the same settings.

Thanks for the information.

[g8gxp]

Interesting... I have my p3 hooked up to a meanwell driver, which takes a full 0-10v. My lights also do not have a gradual on. From 1-10% they will stay off but will flick on at 11% under the illumination control. From 11-100% is pretty smooth but again at ramping down once you dip below 11% it is full off. Is there not a way to get it to begin at 1%?

[ReefEnabler]

I wonder how the profilux is generating the 0-10v signal, does it use internal PWM??? If so, maybe the duty cycle is too slow such that one click away from that 10% range doesn't give it enough juice to start up?

I was reading an instructibles guide, and the author ran into the same issue with the 0-5v output from an alarm clock; he suspected the duty cycle was too long so he used an amtel to convert the PWM input into a new, cleaner PWM output signal that could be adjusted in 1 us increments.

http://www.instructables.com/id/Blue-LED-dawn-simulator-for-Soleil-Sun-Alarm/step4/About-the-LEDs-and-driver/



I might try something like this using an arduino with a much faster duty cycle.

[dipan]

I don't understand why the voltage should drop - this is not usual, otherwise we had many complaints about not smooth dimming in some ranges

10mA is the minimum, if the load is too high possibly the 0V or 10V can't be reached (this depends on the input circuit of the LED-driver)

Hmnnn ... I thought the max current allowed per channel was 10mA. I believe I read this on a thread in this forum. If it's not 10mA, then what is the max current that can be drawn per dimming channel? Is this the same for P2 and P3?

[Matthias]

this was a typo, of course I meant "maximum"

the voltage is quite stable (noise about 5mV), of course we use analogue filters behind the PWM to get a DC voltage
standard ballasts (for tubes) never had a problem
maybe you add a small capacitor < 1uF?

[g8gxp]

Well, this stuff is starting to get a bit over my head. If anybody figures out a way to get a smoother curve during power up instead of the instant on/off, let me know. I'll gladly pay someone for a fix - not really comfortable making something for microcontrolling.

Thanks