- Mon Jul 02, 2018 3:34 am
#76783
Don't be put off though, just use a bare ESP12F instead of nodeMCU. I run systems just like you describe, sending temperature/humidity/supply voltage and alarm data to a pi server, running from batteries. Three ni-MH cells gives a nominal 3.6V (3.8 when freshly charged) and utilising deep sleep, which is very easy to impliment, runs for a time not yet determined. Currently running for 5 weeks and supply voltage has only dropped to 3.61V
Although the specs show a max VCC of 3.6v, there are lots of reports that VCC can be up to 4volts without problem. (NOT digital inputs though which should be kept at 3.3v). I can't guarantee this but I have had no ESP12F failures with three AA size ni-MH cells providing power for this application. The whole thing can be assembled in a very small package.
Mike.
Although the specs show a max VCC of 3.6v, there are lots of reports that VCC can be up to 4volts without problem. (NOT digital inputs though which should be kept at 3.3v). I can't guarantee this but I have had no ESP12F failures with three AA size ni-MH cells providing power for this application. The whole thing can be assembled in a very small package.
Mike.
