ESP8266 Community Forum

- Wed Feb 10, 2016 11:47 am #40860 Hi,
i could send my esp to deepsleep successfully for 30 minutes in each iteration,
i.e: ESP.deepSleep(1800000000, WAKE_RFCAL);
i am sure that it is in deepsleep for 30 minutes. after each wakeup it is processing some data and sending to server. i can see the information in database for every 30 seconds interval. may be ur esp sdk version is not the latest.

Thanks.

- Sun Apr 08, 2018 2:45 pm #75222 With ESP8266-Arduino 2.4.1+ you can get roughly 3.5h of deep sleep at a time.

2.4.1 gives you access to optimized Espressif SDK functions that were introduced in SDK 2.1. Arduino offers `ESP.deepSleepMax()` to determine the max value you can pass to `ESP.deepSleep`. However, as this is based on the RTC and since the RTC clock period tends to drift with changes in temperature this varies a bit.

See https://github.com/esp8266/Arduino/pull/4234 and https://www.espressif.com/sites/default ... df#page=28 (3.3.9. `system_deep_sleep`) for details.

For tricks to reduce power consumption take a look at https://thingpulse.com/2018/03/12/5-hac ... -run-time/

https://frightanic.com/
https://nodemcu-build.com/
https://github.com/marcelstoer/nodemcu-pyflasher