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

[AshwinRavi]

I have 10 ds18b20 sensors on my pi - all on the same pin. No issues using default rasbian settings

could you please walk me through how you set your reef-pi up and your telemetry.

 

[Ranjib]

I originally had the probes hooked up GPIO3 and GPIO4, but after reading through the adafruit tutorial, connected them in parallel like this, to just GPIO 4, sharing a 4.7K resistor.

sorry if the pictures are crappy, once I figure out everything on the software and, I was planning to clean up the wiring.

Pictures are awesome . It is the gpio settings that I was looking for.

Well, if raspbian can support multiple probes, I dont see any reason not to support them in reef-pi. The only challenge I see with multiple probes is how can I detect what device (in raspbian , /sys/bus .. ) represent which probe. i.e. from reef-pi I can detect that there are multiple probe and show temperatures from all of them, but it will be hard to say which one represent the sump , which one tank etc... thoughts? or it does not matter ?

 

[Ranjib]

Multiple temperature sensors can be extremely useful. I have tons of temperature sensors on my tank. Here are a few useful/fun tricks you can do with multiple temperature sensors.

sump temp 1 != sump temp 2: one of the sensors has failed probably a good idea to turn off the heater if either is high.
tank temp != sump temp: sump pump failure: send me an urgent email
room temp < stand temp: speed up stand ventilation fan
metal halide temperature = room temperature: lights are not on - if they are supposed to be cut power and then turn power back on to reboot.

Sorry if I was not clear, I am sure that multiple probes will be useful , its just that the stock raspbian kernel (when I last checked) didn't support multiple ds18b20. Looks like this is not the case any more,, i think the patches I noticed last time in raspbian kernel mailing list is now merge (debian stretch release version) ..

I stand corrected :0) , and I am happy about that

 

[Ranjib]

could you please walk me through how you set your reef-pi up and your telemetry.

reef-pi wont work with multiple probe. I can walk you through single probe telemetry integration, if thats something useful,

 

[AshwinRavi]

Pictures are awesome . It is the gpio settings that I was looking for.

Well, if raspbian can support multiple probes, I dont see any reason not to support them in reef-pi. The only challenge I see with multiple probes is how can I detect what device (in raspbian , /sys/bus .. ) represent which probe. i.e. from reef-pi I can detect that there are multiple probe and show temperatures from all of them, but it will be hard to say which one represent the sump , which one tank etc... thoughts? or it does not matter ?

what about labelling them as sump and display on telemetry once I figure out which one is which physically? is that viable?

 

[AshwinRavi]

reef-pi wont work with multiple probe. I can walk you through single probe telemetry integration, if thats something useful,

i guess I got confused, I have reef-pi working with 1 probe and telemetry added just fine. Thanks.

 

[Ranjib]

i guess I got confused, I have reef-pi working with 1 probe and telemetry added just fine. Thanks.

hmm.. so , its fine if reef-pi just shows the physical address of individual probe, and let you add a label (sump, DT etc) for each one of them .. ?

 

[cypho]

could you please walk me through how you set your reef-pi up and your telemetry.

I started with a PiB (original) in early 2015. Later updated to Pi2B and now on Pi3B. Never had any problems with multiple temp sensors. Default raspbian install. Just wire them in and they all show up in the /sys/bus/w1/devices folder. One of the few things that worked on my first try.

Wired like this. https://learn.adafruit.com/adafruits-raspberry-pi-lesson-11-ds18b20-temperature-sensing/hardware

The DS18B20 "1-wire" sensors can be connected in parallel - unlike nearly any other sensor sold! All sensors should share the same pins, but you only need one 4.7K resistor for all of them

Here is the python code i use to read the sensors

    def read_sensor(self):
    
        lines = self._read_temp_raw()
        if lines is None:
            raise ValueError("sensor returned no data".format(lines))
        if lines[0].strip()[-3:] != 'YES':
            raise ValueError("cannot find Yes in: {0}".format(lines))
        equals_pos = lines[1].find('t=')
        if equals_pos == -1:
            raise ValueError("cannot find t= in: {0}".format(lines))
        temp_string = lines[1][equals_pos+2:]
        temp_c = float(temp_string) / 1000.0
        if temp_c > 80 or temp_c < 1:
            raise ValueError("temperature out of range: {0}".format(temp_c))
        else:
            return {"C":float(temp_c),"F":float(float(temp_c) *9.0/5.0+32.0)}
 
    def _read_temp_raw(self):
        t = '/sys/bus/w1/devices/' + self._address + '/w1_slave'
    
        if not os.path.exists(t):
            raise ValueError("sensor not found: ".format(self._address))
    
        with open(t, 'r') as f:
            lines = f.readlines()
    
        return lines

 

[Ranjib]

I started with a PiB (original) in early 2015. Later updated to Pi2B and now on Pi3B. Never had any problems with multiple temp sensors. Default raspbian install. Just wire them in and they all show up. One of the few things that worked on my first try.

Wired like this. https://learn.adafruit.com/adafruits-raspberry-pi-lesson-11-ds18b20-temperature-sensing/hardware




Here is the python code i use to read the sensors

    def read_sensor(self):
    
        lines = self._read_temp_raw()
        if lines is None:
            raise ValueError("sensor returned no data".format(lines))
        if lines[0].strip()[-3:] != 'YES':
            raise ValueError("cannot find Yes in: {0}".format(lines))
        equals_pos = lines[1].find('t=')
        if equals_pos == -1:
            raise ValueError("cannot find t= in: {0}".format(lines))
        temp_string = lines[1][equals_pos+2:]
        temp_c = float(temp_string) / 1000.0
        if temp_c > 80 or temp_c < 1:
            raise ValueError("temperature out of range: {0}".format(temp_c))
        else:
            return {"C":float(temp_c),"F":float(float(temp_c) *9.0/5.0+32.0)}
 
    def _read_temp_raw(self):
        t = '/sys/bus/w1/devices/' + self._address + '/w1_slave'
    
        if not os.path.exists(t):
            raise ValueError("sensor not found: ".format(self._address))
    
        with open(t, 'r') as f:
            lines = f.readlines()
    
        return lines

Embarrassed to say that this is a silly mistake made by me. I think I confused the fixed GPIO (4) with multiple probes, and read all the patches that involve hooking up multiple probes in multiple GPIOs. Clearly I am a stupid :0/

Stay put good fellas, patch is coming this week to support multiple probe.

 

[Cary]

I prefer to think that you just overlooked it. Not stupid or silly at all. Don't be so hard on yourself. ;-}

 

[AshwinRavi]

Good evening everyone! I have my heater plugged into one of the 8 channel relays and have it configured on reef-pi and works fine. Is there a way I can control the heater to go on and off depending on the temperature from DS18B20? I see the option to control on reef-pi UI, but not sure how it works exactly.

 

[Ranjib]

Good evening everyone! I have my heater plugged into one of the 8 channel relays and have it configured on reef-pi and works fine. Is there a way I can control the heater to go on and off depending on the temperature from DS18B20? I see the option to control on reef-pi UI, but not sure how it works exactly.

Specify the grio PIN numbers that are controlling the relay which in turn control heater and cooler ( if present). The UI is clunky , and confusing for this. I have changed it two days back, so in latest reef pi you get to choose the cooler & heater from a drop down menu of available equipments

 

[AshwinRavi]

awesome, thanks for the quick response!!!

 

[Ranjib]

Good evening everyone! I have my heater plugged into one of the 8 channel relays and have it configured on reef-pi and works fine. Is there a way I can control the heater to go on and off depending on the temperature from DS18B20? I see the option to control on reef-pi UI, but not sure how it works exactly.

Reef-pi will turn on the heater when temperature goes below the specified minimum threshold and turn on cooler if it’s above the max threshold. The PIN number represents grip pins that are connected to relay

 

[Ranjib]

Reef-pi will turn on the heater when temperature goes below the specified minimum threshold and turn on cooler if it’s above the max threshold. The PIN number represents grip pins that are connected to relay

I you don’t have cooler hooked up ( I us a fan) then assign an unused gpio pin

 

[AshwinRavi]

I you don’t have cooler hooked up ( I us a fan) then assign an unused gpio pin

I have two fans that's constantly on as of now, but I guess no harm in connecting it through one of the relays and assigning it as cooler. Thanks.

 

[Ryan115]

Cary, I'm not sure if you are still stuck on this or not.
My new Pi and SD card are coming in today (I was borrowing the other from a friend).
I will start over from scratch on this new one, and try to set it up completely remotely. I will document as I go for this startup.

 

[AshwinRavi]

Reef-pi will turn on the heater when temperature goes below the specified minimum threshold and turn on cooler if it’s above the max threshold. The PIN number represents grip pins that are connected to relay

Hi Ranjib,

I have the control enabled on temperature tab and I have the heater and fans connected to channel 1(GPIO pin 26) and 2(GPIO pin 19) on the relay respectively.

I also have the heater and fans added to the equipment tab here, and it works perfectly from the on and off toggle switch here.

for some reason, I just couldn't seem to get automatic control going, I played with the minimum and maximum threshold to see if it would kick on the heater or cooler and nothing happens, strangely if the temp goes above maximum threshold, it stops recording temperature. not sure what I am doing wrong here.

 

[Ranjib]

Hi Ranjib,

I have the control enabled on temperature tab and I have the heater and fans connected to channel 1(GPIO pin 26) and 2(GPIO pin 19) on the relay respectively.

I also have the heater and fans added to the equipment tab here, and it works perfectly from the on and off toggle switch here.

for some reason, I just couldn't seem to get automatic control going, I played with the minimum and maximum threshold to see if it would kick on the heater or cooler and nothing happens, strangely if the temp goes above maximum threshold, it stops recording temperature. not sure what I am doing wrong here.

Do you have the log by any chance? I'll test it out tonight again with the version you are using, and confirm if I can reproduce.
Sorry for the pain, and thank you for testing it out.

 

[AshwinRavi]

Do you have the log by any chance? I'll test it out tonight again with the version you are using, and confirm if I can reproduce.
Sorry for the pain, and thank you for testing it out.

please don't be sorry, I should be the one thanking you for all the amazing work you have done!!! I have no technical knowledge what so ever and what you have done here is simply amazing.