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Fibaro rgbw and 12v pump

djeskodjesko Member
in Devices
Has anyone tried to add a 12v water pump to the fibaro rgbw ?  

Want to control my garden water system 

Comments

  • casedacaseda Member
    edited May 2017
    You can't control a DC motor with the rgbw controller, it doesn't dim from 12 - 0 volt.
    But uses a method called pulse width modulation (PWM) this turns on and off the power very quick, so the leds are only on half the time when adjusted to 50%
    But does this so fast the human eye can't see this (+/-248 times a second)
    And longer/shorter the higher/lower the brightness
  • djeskodjesko Member
    ok , will use a regular on/off socket then 

    Thanks
  • stepic7stepic7 Member
    edited January 2018
    caseda said:
    You can't control a DC motor with the rgbw controller, it doesn't dim from 12 - 0 volt.
    But uses a method called pulse width modulation (PWM) this turns on and off the power very quick, so the leds are only on half the time when adjusted to 50%
    But does this so fast the human eye can't see this (+/-248 times a second)
    And longer/shorter the higher/lower the brightness
    Hi Caseda
    what do you mean, Cannot I control a DC relay either if I turn to 100%?
    what about if I insert a diode in between?
    and maybe another one in opposition in parallele to the relay?
    thanks
  • casedacaseda Member
    edited January 2018
    https://learn.adafruit.com/adafruit-raspberry-pi-lesson-9-controlling-a-dc-motor/pwm
    (this uses the raspberry as example, but it works the same, just on 244 mhz instead of 500)

    so sure you could try to do it on 0 and 100%, but don't come to me if it breaks after a year. (just because it looks 100% won't mean it really is 100%)
    and a diode won't do a thing in this matter, you better then get a (big) capacitor to catch the pulses and make it somewhat smooth
  • stepic7stepic7 Member
    djesko said:
    Has anyone tried to add a 12v water pump to the fibaro rgbw ?  

    Want to control my garden water system 
    You can control whatever DC load by converting the PWM to DC by a simple circuit, pls see:
    http://henrysbench.capnfatz.com/henrys-bench/arduino-projects-tips-and-more/arduino-lm358-op-amp-pwm-to-voltage-converter/

    If you remember to tie to ground the output, i.e.:
    The capacitor must go to the + input (and must be inverted) and at the output of the LM358 you will collect a +12V (when you set to 0 the output on the RGBW) and 0V viceversa
    However this is just in principle since the load current depends on the IC used, the LM358 can drive low current loads only, see:
    http://www.ti.com/lit/ds/symlink/lm158-n.pdf
    for larger power see:
    http://www.ti.com/amplifier-circuit/op-amps/power/products.html#p233typ=1000;2000


  • casedacaseda Member
    edited January 2018
    @stepic7 please note that this post is now more then an half year old... But good Googling work after suggesting just a diode
  • stepic7stepic7 Member
    OK thanks, by the way
    are the RGBW inputs 0-10V with +10V maximum  or minimum?
    the question is relevant since the output as well is tied to ground (i.e. 0V) for maximum, i.e. 100% output
    By the way I read it's possible to use a temperature sensor. Which one the  DS18B20?
    How do I connect, do you know any link?
    thanks
  • casedacaseda Member
    The input is maximum 10v, you can go a little higher, but the value won't change from 10v up, as that will just reach the maximum of the zwave value used.

    Don't know where you read about the temperature sensors though, think it can only read anything that gives a value of 0 - 10v, and if that is a temperature or light sensor is up to the user.. 
  • DropsDrops Member

    Just as an Information.

    Since two years I am using three RGBW controllers to directly controll the 12V and 24V magnetic valves of my garden watering system without any issues. Of course the Input has to be 12V or 24V depending on the valves used.

    But to be honest I haven't tried the setup with Homey so far (just Zipabox), but why shouldn't it work woo?

  • stepic7stepic7 Member
    Yes, I know, it should
    I must say I had several problems with the RGBW device
    but now I understood it was my mistake, I thought the output was delivering +12V so I grounded the load on the other end which is wrong since the scheme says the output is low when it is powered and was doing the same mistake for the input which is presumed to be powered when it is high
    Now I can't try since the control is elsewhere, I will know in two months time thou and come back
    hope it's not too late
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