Unable to utilize more that one OneWire Temp Sensor

I have posted in the past about trying to use more than one OneWire Temp Sensor with my BrewPi Spark 3. I previously, it was going to be to just monitor ambient air temp while fermenting. Have another data point. Now, I am adding more equipment, so it has gone from a something that is nice to have, to a must have. I have 4 1 wire temp probe purchase from here. 2 are Triclamp, and 2 are just probes. Each one will work if plugged in by itself. When another probe is plugged in, they all become unable to be read. Any help would be appreciated.

How are they wired, all plugged in directly?

It is possible that 2 cables form a dipole antenna with the center point being the Spark. they can be sensitive to interference then. Using a different cable length or swapping from top to bottom could help in that case.

They are all plugged in directly. I have it where one is on the top and one on the bottom. I did get it working, but it requires that a certain one be plugged in second. I am going to test it and see how long it works for. I assume that the cables on the Triclamps are the same length. I do have one that is only a inch or so, and that will disconnect all the sensors.

That sounds like a broken sensor. Especially when the short one is causing problems.

So I have gotten 2 sensors to stay on for 30-45 minutes, then they both become unreachable. I have the top of the spark setup to display the temps of all 4 sensors. I can plug each in individually, and they run fine, but none of the 4 really play well together. I could see one of the sensors being bad, but not all 4. Could it be the BrewPiSpark itself that it bad?

Here is a video of the sensors being plugged in and unplugged. sorry for the shakiness. I was trying to watch the phone as I was plugging them in, but I lost depth perception while doing that.

Can you give the spark a 12V supply to rule out low power causing issues? How are you powering the pi?

Are any of the sensors self heating?
Also check the sensor plugs and the connectors to see if the springs in the sockets or the plastic of the plugs is bent, causing the to touch each other.

So I moved the spark to a 12v 2A power supply, and nothing changed. The sensors still knock each other offline. The Pi has a high quality power supply, plugged into an outlet. None of the sensors heat up, and the plugs on the sensor look to be fine.

All of the sensors having problems is unlikely.
In an older thread, you said your beer sensor was broken and took the others down.

There are 2 possibilities:

  • The sensors are all damaged, possibly due to a short circuit in the broken sensor
  • Something is wrong with the Spark itself.

If only some of these sensors were connected when the beer sensor broke, the problem is more likely the Spark. I can’t really investigate this remotely. Maybe the quickest way to help you get a working brewery would be to send you a new main board for the spark. If that resolves the problem, ship the broken one back for investigation.

I thought it was the beer sensor initially. So I ordered another, and it showed all the same issues with interacting with he other sensors. I could replace the board, or purchase a new spark. I could do either. And if the new spark doesn’t completely fix the issue, I can run the 2 side by side.

If you have a purpose for a new spark, we can do that too. I’ll include 2 free temp sensors so we can rule that out too.

Then once we know what’s wrong, I can replace what’s broken under warranty or refund.

Whichever is easiest. I am okay with opening up the spark and swapping out boards.