Additional DS18B20 readed as pulse at emonpi, not as T2, T3

On my empnPi running Nov’16 firmare, I’d already one temperature sensor connected at the emonpi RJ45 working fine and getting the readings as “t1”.
Now I’m trying to add additional DS18B20 temperature sensors plugged at the one-wire RJ45 interface.
I’m wiring them at the pins 2 (Vcc), 3 (GND) and 4 (data) of the RJ45 connector of the emonPi.

However, once connected, I’m not getting reading as additional temperature sensors (t2, t3 …) but as pulsecount…

At the log:

2017-04-29 12:12:21,309 DEBUG    RFM2Pi     595 From Node : 5
2017-04-29 12:12:21,310 DEBUG    RFM2Pi     595    Values : [1729, 775, 2504, 227.31, 16.8, 0, 0, 0, 0, 0, 1354]
2017-04-29 12:12:21,311 DEBUG    RFM2Pi     595 Sent to channel(start)' : ToEmonCMS
2017-04-29 12:12:21,312 INFO     RFM2Pi     Publishing: emon/emonpi/power1 1729
2017-04-29 12:12:21,315 INFO     RFM2Pi     Publishing: emon/emonpi/power2 775
2017-04-29 12:12:21,317 INFO     RFM2Pi     Publishing: emon/emonpi/power1pluspower2 2504
2017-04-29 12:12:21,319 INFO     RFM2Pi     Publishing: emon/emonpi/vrms 227.31
2017-04-29 12:12:21,321 INFO     RFM2Pi     Publishing: emon/emonpi/t1 16.8
2017-04-29 12:12:21,324 INFO     RFM2Pi     Publishing: emon/emonpi/t2 0
2017-04-29 12:12:21,325 INFO     RFM2Pi     Publishing: emon/emonpi/t3 0
2017-04-29 12:12:21,327 INFO     RFM2Pi     Publishing: emon/emonpi/t4 0
2017-04-29 12:12:21,329 INFO     RFM2Pi     Publishing: emon/emonpi/t5 0
2017-04-29 12:12:21,330 INFO     RFM2Pi     Publishing: emon/emonpi/t6 0
2017-04-29 12:12:21,332 INFO     RFM2Pi     Publishing: emon/emonpi/pulsecount 1354
2017-04-29 12:12:21,334 INFO     RFM2Pi     Publishing: emon/emonpi/rssi 0
2017-04-29 12:12:21,336 INFO     RFM2Pi     Publishing: emonhub/rx/5/values 1729,775,2504,227.31,16.8,0,0,0,0,0,1354
2017-04-29 12:12:21,337 INFO     RFM2Pi     Publishing: emonhub/rx/5/rssi 0

I double checked the wiring, but looks fine. what else could I check?

How old is your emonPi?

Pin 3 is Gnd only on the early models, on the later models Pin 3 is open-circuit, for consistency you should probably stick to using pin 5 of the RJ45 as Gnd.

so the temp senser may not be properly powered and not being seen by the emonPi.

Or as the pulse counting is done on pin6, if the temperature is causing a pulse count it would suggest you have connected to pin 6 not pin 4 and the 1-wire data stream is being seen as pulses.

Have you restarted the emonPi since connecting the new sensor? the emonPi only looks for devices at start-up and after that new arrivals will be ignored. You will probably need to power-cycle as rebooting the OS will not necessarily resart the emonPi add-on board.

1 Like

Thanks Paul
I bought my emonPi last January. You’re right, changing GND from pin 3 to pin 5 and rebooting by power-cycle the device did the trick and now I’m reading all sensors.


Still some mysterious readings at the pulse sensor.

Thanks!