PH Probe Reading 0

[DylanF1]

Hello, I am setting up my Robo-Tank and BRS PH probe for the first time and having trouble calibrating it/getting it to read a value. As you can see from the reef-pi screen shot the "Current Reading" is always zero.

I read through a few posts and did a few things to try and fix but I can't figure it out. one of the posts stated to run the command i2cdetect -y 1 but I received an error.

It also stated that reinstalling reef-pi using the script described here https://docs.google.com/document/d/1t9ma...5qkcuznso3.

I originally installed reef-pi using this and did it again. I know just enough about this stuff to get myself in trouble so call me a novice when it comes to how all this works but I can follow instructions and learn!

Help would be appreciated

[Rob F]

Hi DylanF1, sorry for taking so long to reply. It looks like I2C isn't enabled, it should have when you ran that install script. Try the following to enable it.

In the Pi SSH terminal window type the following command.

sudo raspi-config

In the menu go down to "3 Interface options"

Then go to "P5 I2C"

Select "Yes" and press enter. It should say it was enabled.

If it asks you to reboot select "Yes", if it doesn't and goes back to the SSH terminal run the command

sudo reboot

Then run the i2cdetect -y 1 command and it should print the list of addresses. If that happens it should work.

[DylanF1]

Hi DylanF1, sorry for taking so long to reply. It looks like I2C isn't enabled, it should have when you ran that install script. Try the following to enable it.

In the Pi SSH terminal window type the following command.

sudo raspi-config

In the menu go down to "3 Interface options"

Then go to "P5 I2C"

Select "Yes" and press enter. It should say it was enabled.

If it asks you to reboot select "Yes", if it doesn't and goes back to the SSH terminal run the command

sudo reboot

Then run the i2cdetect -y 1 command and it should print the list of addresses. If that happens it should work.

Thanks Rob. I did that and it appears to be taking readings now. I'll calibrate the probe when I get a chance and see if it works properly. I also ran into another issue, Outlet 1 and 2 are not working on the power bar. I had it plugged into the Power Bar 1 port. Is there something in the configuration that may be causing that?

[Rob F]

Great, sounds like it should be ok now.

Sorry for the confusion on Outlet 1 and 2, on the main controller there are two backup ports that require a jumper or switch of some type connected before those outlets work, this is a safety feature so the ports turn off if something else fails, good for things like ATO. Here's a link showing what I'm mean.

https://docs.google.com/document/d/157ep...07xjy4285r

All the DC ports have the same feature, you'll see a backup port above each DC port, they need a jumper or switch to work as well.

[DylanF1]

Great, sounds like it should be ok now.

Sorry for the confusion on Outlet 1 and 2, on the main controller there are two backup ports that require a jumper or switch of some type connected before those outlets work, this is a safety feature so the ports turn off if something else fails, good for things like ATO. Here's a link showing what I'm mean.

https://docs.google.com/document/d/157ep...07xjy4285r

All the DC ports have the same feature, you'll see a backup port above each DC port, they need a jumper or switch to work as well.

Thanks again Rob, I forgot about the jumper but I should have known. I remember reading that now.

I have a new issue though, I calibrated the probe at 7.03 and 10.05 and put it in RODI water but the readings appear to be bouncing back and forth to the calibration values. It changed again when I put it back in the storage solution. It looks like the lower value is changing but not the upper.

[Rob F]

Sorry again for taking so long to reply, that's interesting, I haven't seen that before. I think something must have gone wrong during calibration, I don't think the probe or circuit could cause those results. One thing you could try, put the probe in the RODI and open the calibration screen. In the first step enter whatever pH is showing and press calibrate. Then close the calibration window and observe it for a while. If that works try the 2 step again. It's also important not to close the calibration window until both steps are completed. Hopefully this will sort it out.

[DylanF1]

Sorry again for taking so long to reply, that's interesting, I haven't seen that before. I think something must have gone wrong during calibration, I don't think the probe or circuit could cause those results. One thing you could try, put the probe in the RODI and open the calibration screen. In the first step enter whatever pH is showing and press calibrate. Then close the calibration window and observe it for a while. If that works try the 2 step again. It's also important not to close the calibration window until both steps are completed. Hopefully this will sort it out.

What is the difference between the two charts in the PH probe setup?

[DylanF1]

For anyone interested in the solution to the problem I was having it can be found in this post.

https://humble.fish/community/index.php?...elp.18654/

[Rob F]

Hi Dylan, very sorry again you were left hanging, very grateful bishoptf was kind enough to help you sort it out.