You can change the auto power-off time with [: Auto power off]
Setting the Power-off Time/Auto Power Off
To save battery power, the camera turns off automatically after a set time of idle operation elapses. If you do not want the camera to turn off automatically, set this to [Disable]. After the power turns off, you can turn on the camera again by pressing the shutter button or other buttons.
1 Select [Auto power off].
2 Set the desired time.
Even if [Disable] is set, the LCD monitor will turn off automatically after 30 min. to save power. (The camera’s power does not turn off.)