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just FYI, I am running a rpi b+ and running Rasbian Wheezy with Emonhub software.

Hello @nzpaul, 85 or -127 is the value reported if there is an error with the sensor or connection. Are you using the sensor on the board or the external encapsulated temperature sensor?

I have not made any changes to it. I just added a two AA batteries. I looks like it has a DS18B20 soldered onto the board (I ordered it with only a DS18B20).

I have attached the photo of what my board looks like.

Did you get these devices recently? Assuming you did I guess you have a emonTH v1.5 rather than a v1.4? and from the log output I'm also guessing it's a rfm69pi (or rfm2pi with rfm69 fitted) due to the number of faint packets received, Further more I'm guessing you are using the "emonpi" variant of emonhub but I cannot tell if that was purchased on a SDcard from the shop, included as part of a downloaded image or installed from scratch.

Can you show us any node 19 "emonTH" settings in emonhub.conf?

The default of

[[19]]
        nodename = emonTH_1
        firmware = emonTH_DHT22_DS18B20.ino
        hardware = emonTH_(Node_ID_Switch_DIP1:OFF_DIP2:OFF)
        [[[rx]]]
                names = temperature, external temperature, humidity, battery
                datacode = h
                scales = 0.1,0.1,0.1,0.1
                units = C,C,%,V

should convert the values "82 3" from "19 82 3 0 0 0 0 31 0" (node id is 19 and the remaining 10 are 5 integers in byte pairs) to 850 and the scaling of 0.1 results in 85.0 so it would appear the values are not being correctly sent from the emonTH.

Are you running stock firmware? Do you have a FTDI usb programmer? If so you could check the serial output as described at the end of the emonTH page in "Appendix B: Debug Mode / Serial output:"

I believe the value of 85 can suggest an open circuit so you should also check the temperature sensor is fitted?

In this v1.4 image the black 3 legged sensor is located bottom left above the mounting hole

and in this v1.5 image it's the just above the right-hand end 2 terminals of the green connector block

In both situations the sensors flat side should be closest to the PCB edge.

Paul

[EDIT - Started writing this before anyone posted and got interupted by phone call - sorry !! :-) ]

@pb66 

I have the new version judging by the photos. I purchased it last week. I took it out of the case and it looks like it is version 1.5.2.

I plugged in a FTDI programmer and this is the debug output I got:

11
emonTH - Firmware V1.5.1
OpenEnergyMonitor.org
RFM69CW Init> 
Node: 19 Freq: 433Mhz Network: 210
Read fail - Unable to find DHT22 Sensor..trying agin
Read fail - Unable to find DHT22 Sensor for 2nd time..giving up
Detected 1 DS18B20
DS18B20 Temperature: 85.00C, Battery voltage: 3.00V
DS18B20 Temperature: 85.00C, Battery voltage: 3.10V

I am running the emonhub software I installed from github. The reciever is the RFM69Pi 433Mhz Raspberry Pi Base Station Receiver Board. I have another off-the-shelf consumer 433mhz weather station, so that might explain the other traffic on the band.

I am just running the default conf file (with my API key added). This is what it says for Node 19:

[[19]]
    nodename = emonTH_1
    firmware = emonTH_DHT22_DS18B20.ino
    hardware = emonTH_(Node_ID_Switch_DIP1:OFF_DIP2:OFF)
    [[[rx]]]
       names = temperature, external temperature, humidity, battery
       datacode = h
       scales = 0.1,0.1,0.1,0.1
       units = C,C,%,V

I found an old DHT22 clone I had lying around. I plugged it in and this is the output I get:

11
emonTH - Firmware V1.5.1
OpenEnergyMonitor.org
RFM69CW Init> 
Node: 19 Freq: 433Mhz Network: 210
Detected DHT22 temp & humidity sesnor
Detected 1 DS18B20
DS18B20 and DHT22 found, assuming DS18B20 is external sensor
DS18B20 Temperature: 85.00C, DHT22 Temperature: 15.70C, DHT22 Humidity: 63.70%, Battery voltage: 3.10V

I assume the DS18B20 they gave me was a dud.

I would say that is strong probability but it is probably equally possible a firmware glitch is the cause, I don't think the DS18B20 only is a frequent choice so cannot be 100% sure of the characteristics of that part of the firmware, but the sensor is being recognized so must be responding, yes it may have an internal error but it may not be being read correctly or even powered up in time for it's periodical reading.

Hopefully someone with more familiarity of that function will step in or I will explore later if I get chance.

Paul

Can I reflash the firmware? where can I find it online?

nzpaul, I think it probably is a dud DS18B20 although it is unusual. Do the soldering connections on the DS18B20 look ok? We will send out another to you today.

@TrystanLea 

I checked the soldering, it looks ok to me. 

Thanks! Can I paypal you the cost of a DHT22 sensor and you put that in the envolope with it? I might as well play around with that as well (the DHT clone I am using with it now for testing is definitely not calibrated correctly)

My order number is #9192

@TrystanLea  I sent an email to the order support email address.