I followed the circuit of the images, ad made the necessary modifications (copy, paste, and include a new sensor in the code) in the sketch.
It runs perfect for two and three sensors. However, when i try to include a fourth one (or more), it start to have problems... because when i heat one sensor, the serial shows that the temperature increase in two of them... heating other different sensor, the temperature showed in the serial seems to increase in other two sensors... so rare. I tested the circuit a lot of times, changed the sensors, etc. But it runs for three but not for more ds18b20 sensors.
So, somebody have a running code for take temperatures of more than three of these sensors by the use of 1-wire circuit?
Thats interesting .
I have noticed with just 2 sensors they run well on 5.0V so it might be worth trying that with 4 or 5 sensors.
You are sure that power comes through the resistor and the center wire of each sensor is attached to that common line and your read wire back to the adrduino is on that line also and nothing else?
The other two wires of all devices must be earthed and that earth runs to the arduino.
Also how are you heating them ie a blowtorch will affect everything around it
The circuit runs perfectly also for three sensors. The problems start with more (i tried with 4 and 5, but my device should have at about 8 or so).
I am heating them with my fingers. The room is about 20-22ºC, so when you take one of the sensor between your finger (meanwhile they are connect to the breadboard, of course), without disturb the other, the temperature increase in this sensor, as seen in the serial screen. The temperature increase quickly to 30 or 33ºC, meanwhile the others remain stable. When i leave the sensor, the temperature goes down again meanwhile the others also remains stable. So until this point, everything is perfect.
However, when i connect more than three sensors, the temperature increase in two of them (with the exact temperature, so is not a disturbance of the environment around the sensor). In fact. They do it by couples. So if i touch sensor 1, sensors 1 and 3 increase the temperature. If i touch sensor 2, sensors 2 and 4 increase the temperature... so this is clearly something related to the circuit and not to the disturbance of the environment.
I copied the circuit from the images provided in the link that i showed in the first post, and they only use three sensors. what i made is to clone the circuit increasing a new sensor following the same idea (pins + and - connected to ground, and data pin to the same line than the other sensors).
Yes OK I have nothing to offer you then ,I merely wanted to make sure you had it right and it sounds like you do. I can't duplicate this as I only have 2 devices on hand. I will be getting more but that could be a month down the track. If the post is not answered then I will post a result as I intended overkill with about 6 of them to operate on the same line in my project which is a boat alarm system
I exported the model with gandaldfs b3d exporter and loaded in irrEdit 1.4. In irrEdit i needed to apply the texture in the models texture tab, and set it to trans_alphack myself. It does not look better with trans_alphack_ref or any other setting. the wire on dvd