Whilst doing some checks for the Can't +++ into EmonTH V2 March 2018 batch thread I happened to leave a totally stock emonTh ticking over with a serial connection. Here’s the output
OpenEnergyMonitor.org
emonTH FW: V323
No EEPROM config
Int RFM...
RFM Started
Node: 26 Freq: 433Mhz Network: 210
Int SI7201..
SI7021 Started, ID: 21
SI7021 t: 17.99
SI7021 h: 49.88
No DS18B20
'+++' then [Enter] for RF config mode
waiting 5s...
+++
temp:180,humidity:498,batt:4
temp:179,humidity:495,batt:4
temp:179,humidity:494,batt:4
temp:178,humidity:493,batt:4
temp:178,humidity:496,batt:4
temp:178,humidity:494,batt:4
temp:177,humidity:499,batt:5
temp:177,humidity:504,batt:5
temp:176,humidity:500,batt:5
temp:176,humidity:501,batt:5
temp:175,humidity:501,batt:5
temp:175,humidity:501,batt:5
temp:175,humidity:501,batt:5
temp:174,humidity:502,batt:5
temp:174,humidity:503,batt:5
temp:174,humidity:504,batt:6
temp:173,humidity:505,batt:6
temp:173,humidity:506,batt:6
temp:173,humidity:507,batt:6
temp:173,humidity:510,batt:6
temp:173,humidity:511,batt:6
temp:173,humidity:510,batt:6
temp:172,humidity:510,batt:6
temp:172,humidity:509,batt:6
temp:172,humidity:509,batt:6
temp:172,humidity:510,batt:6
temp:172,humidity:510,batt:6
temp:172,humidity:511,batt:6
temp:172,humidity:511,batt:7
temp:171,humidity:512,batt:7
temp:171,humidity:512,batt:7
temp:171,humidity:512,batt:7
temp:171,humidity:512,batt:7
temp:171,humidity:512,batt:7
temp:171,humidity:513,batt:7
temp:171,humidity:515,batt:7
temp:171,humidity:514,batt:7
temp:171,humidity:514,batt:7
temp:171,humidity:515,batt:7
temp:171,humidity:524,batt:7
temp:172,humidity:533,batt:7
temp:172,humidity:538,batt:7
temp:172,humidity:545,batt:7
temp:172,humidity:527,batt:7,pulse:4
temp:172,humidity:530,batt:7,pulse:4
temp:172,humidity:519,batt:7,pulse:4
temp:172,humidity:524,batt:7,pulse:4
temp:173,humidity:517,batt:7,pulse:4:
There are no batteries fitted, it is powered via the USB-programmer from the PC’s USB. Just to check, I tested the voltages at the 6way screw term block and the voltage is a steady 5.05V.
Originally I was trying to work out why is the voltage so high? and why is it an integer?
But then it dawned on me it’s most likely 0.7 volts leaking back through the voltage reg and step-up optimizer.
Should that be handled better? eg if value < 1, value = 0, we know the emonTHv2’s stop transmitting at > 1.7v so anything below that will never get sent by RFM.