reef-pi :: An opensource reef tank controller based on Raspberry Pi.

Ryan, Have you seen the PWM to 0-10v analog circuit board on Ebay and Amazon?
https://www.amazon.com/KNACRO-voltage-module-converted-voltage/dp/B01HXRSQF8/ref=sr_1_2?s=electronics&ie=UTF8&qid=1510230874&sr=1-2&keywords=pwm+0-5+to+analog+0-10v

I looks too good to be true. Any thoughts?


Ranjib,

No, I didn't delete the database file. I will do that tonight...have to look up the delete command and variables today.

;-{
Later boys and girls

If something like this would work, I would absolutely use this over making my own circuit. I will be using the guts of a light from SBReefLights, and from what I can tell they run off a 10V analog signal.
 
If you give one a try, let us know how it works. I could get one and hook it up and measure the output with a multimeter, but I don't have the light to test it with yet.

I like the pre-made for the simplicity and neatness of it. I have no issues with building the circuit myself, and I have all the parts needed, but this would be far neater than any board I would create myself.
 
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That's a good find. I don't need 8 channels for lights, but I wonder if some of them could be used to control fan speeds. THAT would be very useful.
 
Ryan, Have you seen the PWM to 0-10v analog circuit board on Ebay and Amazon?
https://www.amazon.com/KNACRO-voltage-module-converted-voltage/dp/B01HXRSQF8/ref=sr_1_2?s=electronics&ie=UTF8&qid=1510230874&sr=1-2&keywords=pwm+0-5+to+analog+0-10v

I looks too good to be true. Any thoughts?


Ranjib,

No, I didn't delete the database file. I will do that tonight...have to look up the delete command and variables today.

;-{
Later boys and girls
I stumbled across those a while back, and keeping them as a last ditch effort if PWM and the RC filter fail.

I believe someone else on here had a marsaqua BB running straight off of 10V PWM without issues.
My lights are on the tank, but I have not cracked the case yet. It is currently running on timers (which is all I really "need") but I hope to get the dimming in place soon.
Precedence has gone to my fight with a 50s era craftsman table saw.
 
I stumbled across those a while back, and keeping them as a last ditch effort if PWM and the RC filter fail.

I believe someone else on here had a marsaqua BB running straight off of 10V PWM without issues.
My lights are on the tank, but I have not cracked the case yet. It is currently running on timers (which is all I really "need") but I hope to get the dimming in place soon.
Precedence has gone to my fight with a 50s era craftsman table saw.
reef-pi timer ? or a dedicated timer hardware?
 
That's a good find. I don't need 8 channels for lights, but I wonder if some of them could be used to control fan speeds. THAT would be very useful.
PWM is good enough for most DC fans, you dont need analog voltage source for that, from what I understand
 
I am planning to cut another bug fix release tonight, 0.8.2. It will have several key bug fixes, including
1) Admin buttons [reload/power off/reboot etc buttons were broken]
2) Chart bug fixes (data points in various charts were not sorted by time)
3) API for weekly trend in temperature (no chart yet)
3) Work in progress notifications integration
 
Well, I heard back from the guy from robo-tank.ca, and it wasn't exactly confidence inspiring. I asked if there was an instruction/datasheet for the board and the response was:
I don't have any info on it on paper, what did you need to know? A couple people have used it with varing results. One person was controller some Meanwell drivers but had to add an extra resistor as it wouldn't dim to off until that was installed so you might still require that.
So, basically it sounds like a buy and pray that setup is obvious (which I may still do).

In better news, I wired up the 12v power supply and 5v buck converter. The buck converter doesn't give off nearly as much heat as I expected that it would. Maybe I'll be able to build a totally enclosed enclosure.

EDIT:

Heard more back. Apparently the image on the website is out of date, and the new design has jumpers to configure the output signal. Connecting the inputs and outputs is still a bit mysterious, but I'm sure if someone bought one, they could figure it out.
 
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Well, I heard back from the guy from robo-tank.ca, and it wasn't exactly confidence inspiring. I asked if there was an instruction/datasheet for the board and the response was:

So, basically it sounds like a buy and pray that setup is obvious (which I may still do).

In better news, I wired up the 12v power supply and 5v buck converter. The buck converter doesn't give off nearly as much heat as I expected that it would. Maybe I'll be able to build a totally enclosed enclosure.

EDIT:

Heard more back. Apparently the image on the website is out of date, and the new design has jumpers to configure the output signal. Connecting the inputs and outputs is still a bit mysterious, but I'm sure if someone bought one, they could figure it out.
Yeah, I was trying to get at that in our last discussion, that, its highly likely that you wont need any extra cooling measures, if you choose the IC properly, then its heat dissepation would be way below the threshold where we wont need any fan etc.
Think about all the mobile charger we are using, they all do 110/220 V AC to 5V DC conversion with 1-2 amp output, and in a small form factor.
Unfortunately I dont have any of those blackbox or sbreef style lights to verify.
I'll take the kessil controller for oscilloscope based insepction tonight, and let you all know what i find.
My firm believe is most leds will work just fine with PWM. Some might need analog, which we can get from simple low pass filters, and in rare cases we'll need aboslutely perfect analog output, in which case we'll use an opamp. I am still reading experimenting with this, ... sooner or later we'll get that chicken :-) ;Chicken
 
That's why you're the brains behind this operation. I just like to hook things up and test them. Now that I know how little heat it gives off, I'll go ahead and start designing the enclosure. I'll probably give it some passive vents on the sides, but that should be plenty.
 

IF YOU HAD TO TAKE A REEFING EXAM, WOULD YOU PASS?

  • Yes!

    Votes: 32 45.7%
  • Not yet, but I have one that I want to buy in mind!

    Votes: 9 12.9%
  • No.

    Votes: 26 37.1%
  • Other (please explain).

    Votes: 3 4.3%
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