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

robsworld78

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Just a note to be aware of: each pca9685 has pull-up resistors for the SCA and SDA lines. If you are planning to add more than one board you should remove them on the others as they will be all in parallel drastically reducing the overall resistance. As a result I2C communication will be failing or be inconsistent.
The PCA9685 operates with a supply voltage range of 2.3 V to 5.5 V and the inputs and outputs are 5.5 V tolerant.

And you can connect more than one like this:
1580975133229.png

And give it a proper address. https://learn.adafruit.com/16-channel-pwm-servo-driver/chaining-drivers

If the second pca9685 is in another box that is further away than 1 meter best is to use a shielded cable.
If you have multiple I2C devices connected or want to extend further look at the PCA9507 these work well. Easy to connect and I can confirm 25ft of USB cable is no issue although probably still not a good idea. Still need to remove additional pullups for extra devices.
 
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brandonq81

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Can anyone help me get a Ph Probe setup in Reef-Pi? I am just starting out, and I am stuck. I am using the Atlas Scientific EZO-pH board. I have a Raspberry Pi 3 Model B setup with Reef-Pi version 3.2 for Pi 3. I've enabled I2C on the Pi. I can read from the probe with a basic python program, and I have setup the driver, analog connection and probe. I can calibrate the probe, but when I try to enable the probe I get an error:
1581714115173.png

When I try to add the Ph to the Dashboard:
1581714194680.png

I get the same error and don't see any output: 1581714267242.png
 
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marekd1

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If you have multiple I2C devices connected or want to extend further look at the PCA9507 these work well. Easy to connect and I can confirm 25ft of USB cable is no issue although probably still not a good idea. Still need to remove additional pullups for extra devices.

Nice find. Now this becomes very interesting, remote I2C devices over 2 wire bus + ground. Cat5 should help with capacitance. Looks like spec is quite large. See below.

1581782009033.png


Check this out... https://www.ebay.com/itm/Differential-I2C-Long-Cable-Extender-PCA9600-with-Buck-Converter-for-Arduino/112580563866?epid=2268638844&hash=item1a3653139a:g:XrwAAOSw~RVaGkNP

look at the signal waveform over 300m
 
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Ranjib

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Can anyone help me get a Ph Probe setup in Reef-Pi? I am just starting out, and I am stuck. I am using the Atlas Scientific EZO-pH board. I have a Raspberry Pi 3 Model B setup with Reef-Pi version 3.2 for Pi 3. I've enabled I2C on the Pi. I can read from the probe with a basic python program, and I have setup the driver, analog connection and probe. I can calibrate the probe, but when I try to enable the probe I get an error:
1581714115173.png

When I try to add the Ph to the Dashboard:
1581714194680.png

I get the same error and don't see any output: 1581714267242.png
The stats related errors are benign and will go away after some time. Did you setup the ezo circuit to be used as i2c from uart? You have to do that using their python library.
 

Crustoceous

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I don't know if this has been covered, but I can't find it if it has been. I'm trying to set up a new reef-pi and Inside the Connectors screen there are pins that do not exist according to the interface. For one, I can't assign any analog pins, and pin 2 I get an error saying "Error: inlet test did not get associated with a driver pin: no valid input pin 0: pin 0 unknown". Am I doing something wrong? Other pins I can add, but it seems pin 2 and any analog inputs that I want to assign, I can't because there are none available.
 
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robsworld78

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You win lol. I haven't seen the PCA9600, that's some range. It says it's the high speed version of P82B96 which is a commonly used. I know the PCA9507 isn't the best but very easy to drop inline and you only need one. Differential is definitely better, it splits the signal on two lines which really helps with noisy environments and you can increase the voltage which helps a lot, only downside is you need one on both ends and more conductors.
 

marekd1

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You win lol. I haven't seen the PCA9600, that's some range. It says it's the high speed version of P82B96 which is a commonly used. I know the PCA9507 isn't the best but very easy to drop inline and you only need one. Differential is definitely better, it splits the signal on two lines which really helps with noisy environments and you can increase the voltage which helps a lot, only downside is you need one on both ends and more conductors.
The PCA9507 is plenty for reef-pi application. I doubt anyone would need 300 meters distance. This opens bunch of new doors for distributed control out of central hub. Very very cool!!! I could have my monitoring probes talk over I2C without probe coax extensions.
 

marekd1

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The PCA9507 is plenty for reef-pi application. I doubt anyone would need 300 meters distance. This opens bunch of new doors for distributed control out of central hub. Very very cool!!! I could have my monitoring probes talk over I2C without probe coax extensions. Now if we could get the I2C inputs support in reef-pi soon, then this will be complete game changer for remote sensing. Ranjib pressure is on :) Just kidding. When ever you are ready :)
 

robsworld78

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The PCA9507 is plenty for reef-pi application. I doubt anyone would need 300 meters distance. This opens bunch of new doors for distributed control out of central hub. Very very cool!!! I could have my monitoring probes talk over I2C without probe coax extensions.
The system would be more reliable with coax extensions vs I2C runs. I2C was never designed to leave the circuit board as the protocol has no error proofing built in and noise is it's worse enemy but yeah using these buffers go a long way.
 

rackley

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Spent the last couple of weeks sourcing and building my reef-pi. Very excited to have it all up and running. Question though: I have the optical sensor for ATO and have a float installed just above the optical level as a back up. What's the recommended way of configuring the optical as primary input control for ATO, while using the float as an override to shut off the ATO? Can that be set up with the macro functionality?

IMG_20200213_000032.jpg
IMG_20200213_050951.jpg
 

Bigtrout

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Spent the last couple of weeks sourcing and building my reef-pi. Very excited to have it all up and running. Question though: I have the optical sensor for ATO and have a float installed just above the optical level as a back up. What's the recommended way of configuring the optical as primary input control for ATO, while using the float as an override to shut off the ATO? Can that be set up with the macro functionality?

IMG_20200213_000032.jpg
IMG_20200213_050951.jpg
Nice looking install!!!

I would not try to use reef pi macro as your failsafe. I would do that in wiring. How do you have the optical wired?
 
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lilgrounchuck

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Can anyone help me get a Ph Probe setup in Reef-Pi? I am just starting out, and I am stuck. I am using the Atlas Scientific EZO-pH board. I have a Raspberry Pi 3 Model B setup with Reef-Pi version 3.2 for Pi 3. I've enabled I2C on the Pi. I can read from the probe with a basic python program, and I have setup the driver, analog connection and probe. I can calibrate the probe, but when I try to enable the probe I get an error:
1581714115173.png

When I try to add the Ph to the Dashboard:
1581714194680.png

I get the same error and don't see any output: 1581714267242.png
It doesn’t have any data yet. All of my sensors kicked that error when I first enabled them. Once it’s enabled an starts recording data it should go away.
 

marekd1

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The system would be more reliable with coax extensions vs I2C runs. I2C was never designed to leave the circuit board as the protocol has no error proofing built in and noise is it's worse enemy but yeah using these buffers go a long way.
Agreed that I2C was never designed to leave the circuit board but for non critical applications like parameter measurement this could be sufficing. Keeping in mind noise sensitivity and lack of error proofing real implementations success will vary. What would be nice is ability to connect reef-pi with say Arduino Mega over serial and this would allow easy remote I/O and I2C expansion with many more I/O lines than available on Raspberry Pi.

Ranjib mentioned in the past posts that this may become reality but it all takes time. I wish I could contribute on the software side but I am purely hardware guy with some software skills. :(
 

Matevz Savarin

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Is this a bug in dashboard or my pump was working at 0:00 for 30s ? I have it set up for 10s at 80% thats 8ml of fluid 4 times a day..
But dashboard says it was working 30s.

BC1377BE-5684-425C-84E3-EE85C682AEBB.png 628D93AE-9958-44D3-9A9D-305EB73B719C.png
 
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cwalton00

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Spent the last couple of weeks sourcing and building my reef-pi. Very excited to have it all up and running. Question though: I have the optical sensor for ATO and have a float installed just above the optical level as a back up. What's the recommended way of configuring the optical as primary input control for ATO, while using the float as an override to shut off the ATO? Can that be set up with the macro functionality?

IMG_20200213_000032.jpg
IMG_20200213_050951.jpg
what is this case?
 

elysics

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what is this case?
google for waterproof transparent junction box, theres thousands of them in all possible sizes. Just dont expect the IP waterproofing ratings to not be lies if you buy a cheap one, though you probably wouldn't go through the effort to keep those ratings anyway.

Consider whether you actually want to see the innards though. Depending on how clean your wiring is and how many components with LEDs are in there, it can look cool and techy or like an annoying blinking entangled mess. I chose the plain grey, non-transparent version.
 
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Des Westcott

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Spent the last couple of weeks sourcing and building my reef-pi. Very excited to have it all up and running. Question though: I have the optical sensor for ATO and have a float installed just above the optical level as a back up. What's the recommended way of configuring the optical as primary input control for ATO, while using the float as an override to shut off the ATO? Can that be set up with the macro functionality?

IMG_20200213_000032.jpg
IMG_20200213_050951.jpg
I also have a safety float switch above my normal running level. I run this completely separately from reef-pi and use it to cut power to all my ATO related 12V systems
 

Matevz Savarin

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Cwaltoon00 I gave up on macros for ato safety function. Just didnt work. Just do it like Des westcott said, put one float above water line and if relay or sensor fails, float will cut off power to ato pump. This is 100% safety feature, regardless reefpi and outlets..
 

marekd1

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Cwaltoon00 I gave up on macros for ato safety function. Just didnt work. Just do it like Des westcott said, put one float above water line and if relay or sensor fails, float will cut off power to ato pump. This is 100% safety feature, regardless reefpi and outlets..

Hopefully no one is using the little float switches (reed magnetic switch) to switch 110V for ATO pumps as a sensor fail safe. One, you would have 110V in a salt water. Two, these were not designed to switch 110V. Always use property matched relay to switch 110V and use 12 or 24V on the relay coil through the float switch to control the relay action.

Just want to make sure no one get hurts sticking their hand in the tank and the sensor is bleeding power in to the water.
 
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