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

Bigtrout

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Quick question I finally purchased a PH probe and trying to calibrate it but the longer I leave the probe in the calibration liquid it never seems to bottom out, the numbers keep going down ever so slowly. How long should you leave the probe in the liquid before it settles on a number, I could have dodgy calibration fluid but it just does not seem to settle.

Thanks :)
I had a similar issue when I calibrated, let each one go 15-20 mins and called it good. I noted calibration at 4, 7 and 10... the slopes were the same so it wouldnt have mattered if id have used 4 and 7, 7 and 10 and 4 and 10, as all results from all three were so similar, i wouldnt have been more that .05 off no matter which calibration pair I chose.

With co2 in my tank at a known rate thru a flowmeter, and a good kh test, i can now predict where my ph will drop when injecting co2, and where it will rise to as it off gasses overnight. And my numbers hold well to the hamas reef co2 calculator, so I know my ph probe is pretty dang close.

I recheck cal every 6 months and with a year and a half old probe I havent had to recalibrate. Saltwater mileage may vary of course.
 

Yov

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reef-pi keeps forgetting the I2C sensors...
1598340504505.png

If i reboot (power off/on) i find them again. but after some time he forgets.
 

stefanm

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reef-pi keeps forgetting the I2C sensors...
1598340504505.png

If i reboot (power off/on) i find them again. but after some time he forgets.

Is that for the temperature sensors?

I had that issue, turned out to be a poor contact I think it was the resistor.
 

lmm1967

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I posted in my thread, it turned out to be that raspberry pi wifi was the issue. After I placed the raspberry on ethernet, it worked perfectly.

I had a problem where wifi on my RPi was going to sleep and becoming non-responsive for a few seconds.

Here is how I fixed it:
1. ssh to RPi
2. Edit /etc/rc.local and add
iwconfig wlan0 power off to that file at the very end but BEFORE the line that says exit 0

3. Reboot and run iwconfig from command line and make sure you see:
Power Management:eek:ff under your wlan interface.
 

lepetitnicolas

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I have not tried this, if it works like normal digital input then it should fine. Otherwise we have to do some software work

hello,

I finally received the sensors two weeks ago just before my holidays.
I just had the time to do some tests with an arduino ... the small sensor seems not to be very reliable (i bought the three different sensor ! )
( Non-contact_Liquid_Level_Switch_SKU_FIT0212-DFRobot )
to be tested with a raspberry and reefpi. I'll keep you informed.

have a good day
 

lmm1967

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Building out a Robo-tank with RPi 4b. I'm back 1 level on Raspberry kernel, reef-pi 3.4.

Only PH & temp probes connected so far.

I keep getting this....

Temperature sensor failure. Error:read /sys/bus/w1/devices/28-0416910aa4ff/w1_slave: interrupted system call

I see some people went to 3.3 on reef-pi but that was a couple months ago - anyone know of a permanent fix?
 

dmolavi

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Building out a Robo-tank with RPi 4b. I'm back 1 level on Raspberry kernel, reef-pi 3.4.

Only PH & temp probes connected so far.

I keep getting this....

Temperature sensor failure. Error:read /sys/bus/w1/devices/28-0416910aa4ff/w1_slave: interrupted system call

I see some people went to 3.3 on reef-pi but that was a couple months ago - anyone know of a permanent fix?

I'm curious about a fix on the temp probes too. I'm holding off on upgrading to 3.4 even though I want the DLI driver that it offers...
 
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Ranjib

Ranjib

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I'm curious about a fix on the temp probes too. I'm holding off on upgrading to 3.4 even though I want the DLI driver that it offers...
I think the temp sensor issue has more to do with raspberry pi kernel . We do nothing more than just reading the device file . And there’s not much change happened in that code path. I have not yet able to detect any ds18b20 sensor with the new pi kernel :-( , still diagnosing
 

lmm1967

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I think the temp sensor issue has more to do with raspberry pi kernel . We do nothing more than just reading the device file . And there’s not much change happened in that code path. I have not yet able to detect any ds18b20 sensor with the new pi kernel :-( , still diagnosing
Does it seem limited to a model of RPi ? I don't have this on my 2 setups using a Pi Zero - just on the Pi4
 
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Ranjib

Ranjib

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Does it seem limited to a model of RPi ? I don't have this on my 2 setups using a Pi Zero - just on the Pi4
for me its only pi4+raspberry pi os. All the older pi 3a/3b/zero are fine, running on raspbian buster.
 

Bigtrout

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I've read about some heat issues with the 4 so I think I might start with a 3b+
My reef pi controls alot and is happily chugging along on a 10 dollar pi zero w...no issues to speak of. @Ranjib and others can attest to the fact that a pi zero w is plenty for what reef pi does.
 

robsworld78

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hello,

I finally received the sensors two weeks ago just before my holidays.
I just had the time to do some tests with an arduino ... the small sensor seems not to be very reliable (i bought the three different sensor ! )
( Non-contact_Liquid_Level_Switch_SKU_FIT0212-DFRobot )
to be tested with a raspberry and reefpi. I'll keep you informed.

have a good day

Thanks for reporting that sensor isn't very reliable, what was the problem with it? I've been using this one and it seems pretty solid, is this one of the others you bought?


Remember the Pi is only 3.3v tolerant, if you power sensor with 5v it'll put that out too.
 

theatrus

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Remember the Pi is only 3.3v tolerant, if you power sensor with 5v it'll put that out too.

This is the most common issue I see with wiring the DS18B20 to the Raspberry Pi - Using 5V for the pullup, but then connecting to an RPi Pin which is very much not 5V tolerant.

You can power the sensor at 5V, but the pull-up needs to be to 3.3V - the 1-wire bus is Open Collector and can only pull down the pin (it shouldn't ever get to 5V from this split power arrangement). There is usually no advantage to doing this though, except for the fact that many of the DS18B20 clones just don't work like the real Maxim part, so anything can happen.

Technically, the power pin is not at all required as 1-wire has a parasitic power mode, but this is very clearly documented as just not working on many of the clone chips you find in the cheap probe cables.
 

lmm1967

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I just swapped over to a
  • Raspberry Pi 3 Model B Rev 1.2
I'll see what happens.

RPi 3b - Reef-Pi 3.4 - latest and greatest kernel.

As we know - no issues with the connections screen. Previous temp sensor error has changed to:

Temperature sensor failure. Error:EOF

& I'm seeing this occassionally:
Current value of 'FragTemp' is below minimum threshold. Executing up routine
 

Smin

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Yes. For the time being. I think I have fixed the issue with updated raspberry pi os, we are in process of testing it.
If you want anyone else to test it out give me a shout!
I'm tempted to get a pi zero and use the 4 for another project, there seem to be quite a few bugs popping up with it that are is related
 

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