Hi,
I would like to ask you for help.
I have conected LAN CONTROLER as you can see in schematic.
I have got problem, when I switch thermostat contact ON/OFF the value of temperature is jumping UP/DOWN and in finally turn to 127°C.
Doesnt help reboot - value 127°C after reboot still there.
I must disconect power suply, then everithing working(value of temperature is OK), but when I switch thermostat - same prolbem again.
The problem occurs when thermostat switch on/off or off/on, or in both cases?
I am not sure.I have to chek it on the site, but I think about both cases.
Try use flyback diode parallel to relay!
Yes I will do that.
I thought that somebody else had same problem...
You have connected termostat to relay contact on LK?
Disconnect the relay's power and check the sensor reading. If it works - you need to change the cable - the power supply should not be in the same bundle as the sensor.
How long is the connection between LK and the sensor?
Willxt-Yes,thermostat is simply mechanical thermostat mounted on the wall and contact is conected in series connection with OUT0 - as you can see in schematic. Also OUT1 and OUT2 connected in the same way with another two thermostats...
pat - DS18B20 is digital senzor so there should not be a problem with interferences. I have similar connection on diferent site where senzors and power for relay goes in CAT5 cable and there is no problem.
And also on another site - sensors are conected separerly on 4wire tephone cable and sometimes I saw same problem...
But here when I switch thermostat ON/OFF one time the temperature first time reach 80C and then go back to normal value.
But if I switch termostat few times in short time then temperature reach 127C...
you have 12V relay on schematic, what is it for?
It's not about interference of digital signal but the induction of too high voltage on lines DS18 when switching the relay.