I think I have control of the solenoid valves (open/close) down, however there is a third line to control the "flow". This signal requires between 2v - 10v, and for the life of me, I'm not sure how to regulate this voltage. I was thinking a PWM would work here, but from what I can tell, those are for controlling current, not voltage? Or am I wrong in my thinking?
__________________ Primary: Empty Secondary: Empty Lagering: Empty Bottled: Empty Kegged: Empty On Deck: Pink Elephant Delerium Clone, Helles Gutbier, So Kolsch, Apricot Belgian Wit, Fox River Trail IPA, Belgian Slut IPA
A PWM won't work - A PWM controls duty cycle over a period of time. So if your period is 2 seconds, and you set it for 50%, it's 100% on for one second, and 100% off for one second.
You need some sort of variable power supply. I'm not quite sure how you would automate that though...
I found this cool project, which could probably be used for manual control. However, I'm not sure how I would go about automated this...
__________________ Primary: Empty Secondary: Empty Lagering: Empty Bottled: Empty Kegged: Empty On Deck: Pink Elephant Delerium Clone, Helles Gutbier, So Kolsch, Apricot Belgian Wit, Fox River Trail IPA, Belgian Slut IPA
I think I have control of the solenoid valves (open/close) down, however there is a third line to control the "flow". This signal requires between 2v - 10v, and for the life of me, I'm not sure how to regulate this voltage. I was thinking a PWM would work here, but from what I can tell, those are for controlling current, not voltage? Or am I wrong in my thinking?
I can't help with the flow control issue, but I am wondering what it is that you are controlling. I think that valve is designed for liquid flow control. You might be facing some clogging issues if you are using it to control the flow of wort from a MT. Some particulates inevitably make it into the loop and can clog any restriction points very easily. Clear water would not be a problem, but wort certainly may be. Probably would not be suitable for gas control at all. I may have this all wrong, so as usual, YMMV etc.
A fairly simple resistor capacitor network will let you use the PWM output to simulate an analog output. You will need at least 12V signal from the PWM output to work with RC network to reach 10V signal.
Is it common practice to join the AC common line with the negative DC line? I guess I just don't understand that part.
With the LM317, would there still be a way to control the valves via automation (microcontroller)?
Sorry for the noob questions, I'm trying to wrap my head around all this prior to buying the electrical side of my rig. Gah I wish I would have learned more electrical engineering in school now .. bah!
__________________ Primary: Empty Secondary: Empty Lagering: Empty Bottled: Empty Kegged: Empty On Deck: Pink Elephant Delerium Clone, Helles Gutbier, So Kolsch, Apricot Belgian Wit, Fox River Trail IPA, Belgian Slut IPA
Is it common practice to join the AC common line with the negative DC line? I guess I just don't understand that part.
no its not, i didn't pick up on that untill you mentioned it
Quote:
Originally Posted by TriangleIL
With the LM317, would there still be a way to control the valves via automation (microcontroller)?
no, that would be for a manual operation. you need some kind of d to a converter. Simplest would be what kladue suggested, but would have to be played with to get the right values and your mcu would have to use resources to make the pwm happen. (depending on your mcu some have a couple of channels built in) second option would be to use a chip dac (providing your mcu doesn't already have one built in) your program would write a value to the chip and the chip keeps the value constant.
Quote:
Originally Posted by TriangleIL
Sorry for the noob questions, I'm trying to wrap my head around all this prior to buying the electrical side of my rig. Gah I wish I would have learned more electrical engineering in school now .. bah!
not at all
thinking bout it more: most of the chip dacs have a max out of 5v (or at least the really cheep ones i was looking at) so that would men you would also need and op amp to boost the Vout to the 10 v. one could hand wire that but it would be better for a pcb. so if you want a quick and dirty use the switched cap method. if you are planning to etch a pcb i would go with the chip
Solenoid Valve Control - Help!?
Linear Mode
