1-wire sensors lost after some time
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1-wire sensors are lost after some time of usage.
for example the recorded data (via node-red to influxdb):
i tried to reboot via ssh (M203 Module), this doesn't help (after the last points near 07:45).
There is no issue in the file systems with the used MicroSD card (SanDisk Extreme Pro)
the evok webinterface shows N/A for the defined sensors in the evok.cfg
For cabling i use a 2x2x0,8 EIB cable. Cable length are different to the sensors (in a range of 5-15 meters)
later i'll take pictures of the wiring points to ensure all things are ok.
( I think there is some issue in the 1-wire port or evok ) -
One DS18B20 is faulty. To discover this one sensor was not easy.
Therefore, I have each data line of the sensors (heating) individually connected to the bus and then tested the 1-wire bus. (if the heating sensor data wires are disconnected, the other 2 sensors are transmitting values)
At no time did I disconnect GND and + 5V to a sensor.
Unfortunately the simple connection of the sensor data ware was not sufficient, because EVOK did not deliver any new values.
Only a restart of the module could detect a functioning sensor / 1-wire bus within one minute.
Without restart, the value comes in felt 5-10 minutes, if the bus works well ...6 sensor wires in one clamp, the faulty was there.
The sensor wires are drilled together and then put in the WAGO clamp.
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Hello @christian,
it is hard to see from the picture, but it looks like your sensors are connected in star topology. This is highly unrecommended and you can read more about it here: https://www.maximintegrated.com/en/app-notes/index.mvp/id/148Best regards,
Martin
