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

[rushbattle]

So, an interesting thought I had today. I dabble in Radio controlled cars as one of my other money pit hobbies. The brushless motors are controlled my an electronic speed control that I assume takes a PWM input from the radio receiver. I wonder if there are some pre built ESC that can be interfaced with the pi's PWM?

The ESC is a motor controller, just built for RC applications.

 

[b4tn]

The ESC is a motor controller, just built for RC applications.

But I am sure there has to be some sort of pre built ESC comparable with pi. It would be pretty easy to control something with the light program via pwm if there was a brushless driver. Just a quick search.

https://www.amazon.com/dp/B075L7YDR9/ref=cm_sw_r_sms_c_api_i_dhtnCbMX999H7

 

[That Crusso Kid]

There are two main types of brushless motors: sensored and sensorless (back EMF). A controller for one won’t work for the other, especially a sensored controller for a sensorless motor.

Thanks for pointing that out, I was thinking that they are all using back EMF in the aquarium pumps. Are there many BLDC motors used in aquarium pumps with Hall effect sensors?

Did someone say, "EMF?"
Sorry, I couldn't stop myself!

 

[theatrus]

I can't speak for DC aquarium pumps, but (usually) in power tools (think DeWalt and similar drills, etc) that are DC powered, the motors usually have a Hall effect sensor sensing a diametrically magnetized ring on the shaft of the motor. The sensor sends info back to the controller which compensates with more (or less) power to the motor depending on where the trigger position is (which is usually just a slide pot).

The risk here is that if the user says "take it to 11" (or in our case "pump 1000gph"), the controller will give the motor all the electrons it can...so there needs to be some current limiter in there (fuse, resistor, etc) to prevent overloading. I would see this being an issue in aquarium pumps...water and electricity...esp when the lower cost stuff is taken into account. Just like Harbor Freight, they trim costs by eliminating everything that isn't absolutely necessary for the item to function...

It’s not used for current limiting - there is a dedicated sense resistor (or using the fet rds) for that. The sensors are for commutation, so the motor controller knows which of the three Wye coils to energize and by how much. Most small motors using a trapezoidal drive scheme and variable PWM to smoothly move. Without any sensor, the speed controller has no idea where the rotor is or how fast it’s going (or if it’s just bouncing back and forth rapidly).

RC ESCs are the same thing at a different scale. Do they use a Hall effect or just back EMF? I haven’t looked at anything RC for a long long time.

 

[dmolavi]

It’s not used for current limiting - there is a dedicated sense resistor (or using the fet rds) for that. The sensors are for commutation, so the motor controller knows which of the three Wye coils to energize and by how much. Most small motors using a trapezoidal drive scheme and variable PWM to smoothly move. Without any sensor, the speed controller has no idea where the rotor is or how fast it’s going (or if it’s just bouncing back and forth rapidly).

RC ESCs are the same thing at a different scale. Do they use a Hall effect or just back EMF? I haven’t looked at anything RC for a long long time.

The hall effect sensors aren't used for current limiting, but they do send info back to the controller saying "the shaft is rotating at X RPM"...the controller then corrects with either more or less power. The current limiting comes into play to make sure that too much power isn't sent...

 

[Ranjib]

How do I go about adding additional temperature sensors? I keep getting an error on the one I have setup and I want the redundancy. Last night my tank dropped 3 degrees before the sensor stated working again.

its simple and the wiring is same as the first one. One wire (the protocol temperature sensor uses) is a bus . You can attache more than one sensor that share exactly same GND, +Ve and Data wires

 

[That Crusso Kid]

Quick couple of questions for someone new to the thread... @tankaholic

How does one do this?

I'm a pi noob
Also can you change time from military if so how?
thanks

How does one do this?
I'm a pi noob
Also can you change time from military if so how?
thanks

 

[Ranjib]

Quick couple of questions for someone new to the thread... @tankaholic



How does one do this?
I'm a pi noob
Also can you change time from military if so how?
thanks

context?? is this here in r2r thread?

 

[That Crusso Kid]

context?? is this here in r2r thread?[/QUOTE

Yes, it was asked by @tankaholic on someone else's build thread.

 

[b4tn]

@Ranjib, are the fixes listed in the comments below implemented or planed for the 2.x RC.x release? I installed 2.0 when you first released it but have not updated since. I noticed you had 18 comments and the doser calibration fix is in there.

https://github.com/reef-pi/reef-pi/compare/2.0...master

 

[Mendeln]

Yay :) . I’m not sure about the ato sensor , keep us posted on how it goes

i cant use the standard level sensor. the algea will block the moving parts because i have a fresh water aquarium

 

[Ranjib]

i cant use the standard level sensor. the algea will block the moving parts because i have a fresh water aquarium

Hang it upside down?

 

[Ranjib]

@Ranjib, are the fixes listed in the comments below implemented or planed for the 2.x RC.x release? I installed 2.0 when you first released it but have not updated since. I noticed you had 18 comments and the doser calibration fix is in there.

https://github.com/reef-pi/reef-pi/compare/2.0...master

2.1 should have the doser fix . Rest of the things (drivers api in particular will be part of 3.0 alpha/beta series ). It will break all existing api of 2.0.
Is there anything specific you are looking for?

 

[stefanm]

Ok, I think I've got the pi up and running, it's possible I've screwed up something, just browsing the ui I can't seem to add anything, do I need to have stuff connected to add or have I messed up something during the software installation? @Ranjib and others?

 

[Ranjib]

Ok, I think I've got the pi up and running, it's possible I've screwed up something, just browsing the ui I can't seem to add anything, do I need to have stuff connected to add or have I messed up something during the software installation? @Ranjib and others?

Which guide you are following ? Can you be specific about what you tried to do and what did not worked?
Most likely you have to create few outlets , jacks etc (connectors) before using them with equipment , light etc. adafruit guides cover them step by step

 

[stefanm]

Which guide you are following ? Can you be specific about what you tried to do and what did not worked?
Most likely you have to create few outlets , jacks etc (connectors) before using them with equipment , light etc. adafruit guides cover them step by step

Honestly I just had a feel around the ui, now I know how to set it up (software) I think I should probably do it again being as it's my first time with the Linux console. I didn't see many pin options, almost convinced something didn't go right along the way.

https://reef-pi.github.io/additional-documentation/headless/

This is the guide I followed, hopefully the right one for rpi3 model a+

 

[stefanm]

I'll try to set up the temperature sensors tomorrow before panicking, seeing as I just need to connect them as they they're already made.

 

[b4tn]

2.1 should have the doser fix . Rest of the things (drivers api in particular will be part of 3.0 alpha/beta series ). It will break all existing api of 2.0.
Is there anything specific you are looking for?

Thanks, I was looking for the doser calibration fix. I wasn’t sure if you already released it or not. Thanks.

 

[ScottF83]

Evening

Just been setting up reef-pi on a Pi Zero

All going very well and had telemetry and email alerts set up and working.

Then I tried to port forward but I'm already using 80 so I changed reef-pi to be 0.0.0.0:8080

But then I was locked outfrom my address.local dashboard and had to 'rm' the /var/ file to reset the database and start over with the settings

How do I correctly change the port being used?

Many thanks
Scott

 

[ScottBrew]

Evening

Just been setting up reef-pi on a Pi Zero

All going very well and had telemetry and email alerts set up and working.

Then I tried to port forward but I'm already using 80 so I changed reef-pi to be 0.0.0.0:8080

But then I was locked outfrom my address.local dashboard and had to 'rm' the /var/ file to reset the database and start over with the settings

How do I correctly change the port being used?

Many thanks
Scott

Most likely lost the reef-pi.local information. You can login directly with the pi IP address and :80 on the end from your browser, ex: 192.168.0.55:80. If you are on Windows, type cmd in the search bar, then enter. Type arp -a in the cmd box and it should list every connected device on your network. May have to try each number 1 at a time.