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

[ScottBrew]

Only manual dimming for me, but I stagger each panel turning on and off so it's a bit of sunrise sunset in a way, I have 4 of the 165w mars aquas

Ahhhh, thought your Black Box LED controllers were dimmed by the pi.

 

[LionHeart2017]

Ahhhh, thought your Black Box LED controllers were dimmed by the pi.

Nope, never really found an easy to follow guide on them, also the ones I have read about only dim down to 10-15 %
With 3 out of 4 panels on min setting it's enough for my tank on just blues channel

 

[Ranjib]

I can imagine the headaches from it all ranjib, don't burn out man, awsome you share this with everyone

Here's a coral pic or two

Duncan, blasto and pink zippers :-) . Love them.

 

[Des Westcott]

A little UI bug that I've encountered before and I see still persists.....

When editing number fields, if you click on the number and then use the backspace key to remove the numbers/text and you go too far back, suddenly "NaN" appears in the box and you can't get rid of it by backspacing or anything or enter your required values. You then click on another field / tab and then go back and the field has reset and you can proceed.

 

[Des Westcott]

FYI Update to RC3 went without a hitch

 

[Diamond1]

Quick question for any pi gurus out there. I have enough room in my main unit enclosure to add a 2nd pi3, I'm going to use the second unit to run dosing pumps and a ph probe and plan on running cat5 or 1/8"cables to a breakout box with the pumps in it.

Can I run the second pi off of the existing 12v 2 amp power supply or off the 12v rail on the first pi hat or will it be too much for the power supply to handle?
I'm just trying to keep the power bricks around the tank to a minimum but if I need to add another power supply, no big deal.

 

[b4tn]

The recommended power supply is 2.5 amps for the pi 3. But current is only used as needed so you could get a 100 amp power supply and it would work lol. I would probably double up and get a 4 or 5 amp power supply they are cheap on amazon.

 

[b4tn]

Here is a link. https://www.amazon.com/110V-220V-Co...53&sr=8-1&keywords=12+volt+5+amp+power+supply

 

[MaccaPopEye]

Not safely (at least I dont think so). P=IV so if you need 2.5A (max Pi draw) at 5V you need 12.5W (before any efficiency losses) to power 1 Pi. Powering 2 Pis at 5V 2.5A you would need double that (again before conversion efficiency loss). A 12V 2A power supply is 24W. I'd saw you need at least 12V 3A (assuming an 80% loss from the buck converter).

But it is 4am so I could be wrong haha :)

 

[naoki]

Not safely (at least I dont think so). P=IV so if you need 2.5A (max Pi draw) at 5V you need 12.5W (before any efficiency losses) to power 1 Pi. Powering 2 Pis at 5V 2.5A you would need double that (again before conversion efficiency loss). A 12V 2A power supply is 24W. I'd saw you need at least 12V 3A (assuming an 80% loss from the buck converter).

With RPi 3B+, the power draw is around 5.7W under load (with monitor Wifi etc) and 2.3W when idle (link). Zero has much lower power consumption (around 1W). Also, most of the step-down coverter has efficiency > 90%, I thought. If other peripherals connecting to the PS aren't drawing too much, the power supply can easily support 2 RPi 3B+.

 

[MaccaPopEye]

With RPi 3B+, the power draw is around 5.7W under load (with monitor Wifi etc) and 2.3W when idle (link). Zero has much lower power consumption (around 1W). Also, most of the step-down coverter has efficiency > 90%, I thought. If other peripherals connecting to the PS aren't drawing too much, the power supply can easily support 2 RPi 3B+.

Thanks, I just used 2.5A as that is the power supply recommended for the Pi. The 5.7W draw is interesting, I never actually thought to look for that. Makes me wonder why do they recommend a 2.5A power supply minimum? If the max current under load is less than 1.2A then a 2.5A is pretty overkill.

As for the converter I did a quick google and most of them advertise 95% but it depends on the input and output voltage. The larger the conversion the greater the loss. I used 80% as a worst case scenario but it could likely be 90.

Either way if the max current draw of the Pi is only 5.7W then yes the 12V 2A supply would be able to handle that easy.

 

[Ranjib]

Here is a link. https://www.amazon.com/110V-220V-Co...53&sr=8-1&keywords=12+volt+5+amp+power+supply

These are rated for 2 AMP, and can handle upto 3A max

 

[Diamond1]

Thanks for the responses guys. I'm gonna give it a try with 1 power supply. I will do some bench testing this week.

 

[ScottBrew]

2 amps at 12vdc is 24 watts, 2 amps at 5vdc is only 10 watts. Ohms law. I'm pulling 4.3 watts from the pi, the 5v and 24v power supplies but without any pumps or lights on.

 

[Ranjib]

Thanks, I just used 2.5A as that is the power supply recommended for the Pi. The 5.7W draw is interesting, I never actually thought to look for that. Makes me wonder why do they recommend a 2.5A power supply minimum? If the max current under load is less than 1.2A then a 2.5A is pretty overkill.

As for the converter I did a quick google and most of them advertise 95% but it depends on the input and output voltage. The larger the conversion the greater the loss. I used 80% as a worst case scenario but it could likely be 90.

Either way if the max current draw of the Pi is only 5.7W then yes the 12V 2A supply would be able to handle that easy.

This is perhaps my biggest concern when designing aio builds

 

[Ranjib]

@Diamond1 some things to remember:
- the perma proto or perf boards I recommend are rated for 1.2-2 A
- female -female jumper wires we use has current rating of 1.5 A if they are 28 awg, and 7A if they are 22 awg.
- same goes for solid core wires that we solder as jumpers in the perma proto board. I always recommend 22 awg in guides . Once present , perma proto boards will support 7 amp using these
- lm2596 is rated at 3a, but better design it to run at 2amp or below
- create power rails and draw power from there , instead of daisy chaining , like drawing from pi’s

 

[LionHeart2017]

Is there a reason to use 12v supplies when you can get 5v supplies?

 

[Diamond1]

@Diamond1 some things to remember:
- the perma proto or perf boards I recommend are rated for 1.2-2 A
- female -female jumper wires we use has current rating of 1.5 A if they are 28 awg, and 7A if they are 22 awg.
- same goes for solid core wires that we solder as jumpers in the perma proto board. I always recommend 22 awg in guides . Once present , perma proto boards will support 7 amp using these
- lm2596 is rated at 3a, but better design it to run at 2amp or below
- create power rails and draw power from there , instead of daisy chaining , like drawing from pi’s

Thanks for the heads up. I plan on using 22awg for all the wiring except for the wires running from the head unit to the pumps. For those I'm leaning towards cat5.

 

[pdisner]

Hey everyone. New to the forum and to Reef-Pi. I e encountered a lot of hurdles and the learning curve I’m still climbing. I’m having a problem that I just can’t figure out. I have been able to install and login and start ReefPi. When I go back to my project the next time, I can’t seem to get the server to open. I did everything including a purge and reinstall. When I check the status, It shows me this:

I know it has to be something simple, but I just can’t see it from where I’m standing. Maybe one if you super users can give me a hand past this hurdle? A possible related issue is that I cannot seem to get my ssh to connect. I never have been able to. It’s selected in options. Ive Double checked everything.

 

[ScottBrew]

Hey everyone. New to the forum and to Reef-Pi. I e encountered a lot of hurdles and the learning curve I’m still climbing. I’m having a problem that I just can’t figure out. I have been able to install and login and start ReefPi. When I go back to my project the next time, I can’t seem to get the server to open. I did everything including a purge and reinstall. When I check the status, It shows me this:

I know it has to be something simple, but I just can’t see it from where I’m standing. Maybe one if you super users can give me a hand past this hurdle? A possible related issue is that I cannot seem to get my ssh to connect. I never have been able to. It’s selected in options. Ive Double checked everything.

Looks like https is turned on, I recall reading another thread here about it causing a problem.