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

pais

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Hi everybody, a suggest if you want to implement any other sensor (digital or analogic) is to use an arduino connected via i2c ro the rpi. I'm succesfully using this technique to achieve a reading of both analog ph-meter and an ec-meter. I perform also value-based actions on these sensors. I have seen ranjib talking about the new feature homeostatis, THANK YOU for the great work, now im waiting for that being implemented to reduce the arduino tasks.
 
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Ryan115

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It actually is in a metal enclosure, but the one side is open. And the open side is facing the direction of the router(s)


01d33b2464a3a4de39d225d541cdc9a7c426f6f796.jpg
If you have a direct connection (or if you are getting enough of a signal to remote in to the pi), run this code in terminal to get a report on your signal strength.
Code:
sudo iwlist wlan0 scan | egrep "Cell|ESSID|Signal|Rates"
 

Ernie E

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Totally following should you decide to post any examples of your setup and/or scripts used on the arduino to do the translation!! Which pH probe are you using?


Hi everybody, a suggest if you want to implement any other sensor (digital or analogic) is to use an arduino connected via i2c ro the rpi. I'm succesfully using this technique to achieve a reading of both analog ph-meter and an ec-meter. I perform also value-based actions on these sensors. I have seen ranjib talking about the new feature homeostatis, THANK YOU for the great work, now im waiting for that being implemented to reduce the arduino tasks.
 
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Ranjib

Ranjib

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Hi everybody, a suggest if you want to implement any other sensor (digital or analogic) is to use an arduino connected via i2c ro the rpi. I'm succesfully using this technique to achieve a reading of both analog ph-meter and an ec-meter. I perform also value-based actions on these sensors. I have seen ranjib talking about the new feature homeostatis, THANK YOU for the great work, now im waiting for that being implemented to reduce the arduino tasks.
in this route, where you are primarily using the arduino for analog input, how you do galvanic isolation? reef-pi currently has a HAL Analog driver interface that we can use to implement an arduino driver. We can totally do it if it makes sense (i.e. the results we get are good enough for our use case, and theres enough appetite for such use case)
 
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Ranjib

Ranjib

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Totally following should you decide to post any examples of your setup and/or scripts used on the arduino to do the translation!! Which pH probe are you using?
Without galvanic isolation, this will be highly unreliable, in our experience. My reading would fluctuate a lot when I tried read ph signal directly,
 
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AbjectMaelstroM

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Has anyone used these dosing pumps with Reef pi? Or known if they would be compatible?

 
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Has anyone used these dosing pumps with Reef pi? Or known if they would be compatible?

Not yet, but I would love to. Is available from amazon?
 

AbjectMaelstroM

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hm 5$ extra than ebay, not bad at all. I'll get it and test out. Thanks for the link. Its been long pending.
Can't wait to see the results. I was thinking about using those instead of gutting a slave doser unit. Looks like those are wire for +/- in one direction and +/- in reverse direction. Is there any reason to wire "reverse"? I don't imagine I'd ever need to draw water from the tank....
 
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Ranjib

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Can't wait to see the results. I was thinking about using those instead of gutting a slave doser unit. Looks like those are wire for +/- in one direction and +/- in reverse direction. Is there any reason to wire "reverse"? I don't imagine I'd ever need to draw water from the tank....
From my primitive understanding, we can use reef-pi as it is, with stepper motors. We have to connect pi or pca9685 pwm pin to a stepper drivers (such as drv8835) and that should be it.
Reversing the motor direction is very common. The titration systems definitely use those capabilities. From a manufacturing and electronics perspective, H-brige drivers (a type of circuit that allows easily switch the polarity of motors) are very common and omnipresent in most stepper/dc motor equipment. I guess from manufacturing point of view its hard to know if this feature will be used or not, but given the prevalence (and cheap) of this capability, its safer to just have it.
It will be awesome if @theatrus, @Bigtrout or @Michael Lane can validate my assumption, beforer i embark on testing this setup ;-)
 

rushbattle

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From my primitive understanding, we can use reef-pi as it is, with stepper motors. We have to connect pi or pca9685 pwm pin to a stepper drivers (such as drv8835) and that should be it.
Reversing the motor direction is very common. The titration systems definitely use those capabilities. From a manufacturing and electronics perspective, H-brige drivers (a type of circuit that allows easily switch the polarity of motors) are very common and omnipresent in most stepper/dc motor equipment. I guess from manufacturing point of view its hard to know if this feature will be used or not, but given the prevalence (and cheap) of this capability, its safer to just have it.
It will be awesome if @theatrus, @Bigtrout or @Michael Lane can validate my assumption, beforer i embark on testing this setup ;-)
I am afraid @theatrus is not engaged with reefing for a while now. Perhaps he’s busy, I hope for that and not health issues, or anything else.
 

Michael Lane

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From my primitive understanding, we can use reef-pi as it is, with stepper motors. We have to connect pi or pca9685 pwm pin to a stepper drivers (such as drv8835) and that should be it.
Reversing the motor direction is very common. The titration systems definitely use those capabilities. From a manufacturing and electronics perspective, H-brige drivers (a type of circuit that allows easily switch the polarity of motors) are very common and omnipresent in most stepper/dc motor equipment. I guess from manufacturing point of view its hard to know if this feature will be used or not, but given the prevalence (and cheap) of this capability, its safer to just have it.
It will be awesome if @theatrus, @Bigtrout or @Michael Lane can validate my assumption, beforer i embark on testing this setup ;-)
It sounds like you have it right. Stepper motors are driven by alternating magnetic fields, so it's a bit more complicated than using a DC motor. The stepper driver will control moving those fields with each pulse.
 
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It sounds like you have it right. Stepper motors are driven by alternating magnetic fields, so it's a bit more complicated than using a DC motor. The stepper driver will control moving those fields with each pulse.
As I am reading through, it seem like the duty cycle does not matter that much (anything above 50% is good) and I have to actually change the pwm frequency to change the speed of the stepper motor. I am ordering a DRV8825 driver and that 33$ stepper motor based doser for testing. Thanks for checking :) . I'll keep you all posted
 

MrWheelock

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Can't wait to see the results. I was thinking about using those instead of gutting a slave doser unit. Looks like those are wire for +/- in one direction and +/- in reverse direction. Is there any reason to wire "reverse"? I don't imagine I'd ever need to draw water from the tank....
Auto water change
 

buddy.

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Does anyone know what this email alert is caused by? The probe is still working so I am not sure why it says it failed.

20190910_100151.jpg
 

buddy.

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Looks like it's no longer registering the temp probe labeled "sump".

Check connections/probe, could be a dead probe.
The weird thing is that the probe never actually stops working according to my graphs on the dashboard.
 

AbjectMaelstroM

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The weird thing is that the probe never actually stops working according to my graphs on the dashboard.
Does it actually register temp changes or displays the same temp it read last? When I was playing around with my build, I saw that same message when I disconnected Temp probes with pi running. It continued to display temp reading, but it didn't register changes, but continued the last temp reading.

I would check make sure the probe is functional and registers temp changes.
 
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