GPS - Battery Saver Mode Details

There are two ways in which "battery saver" mode reduces power consumption on Garmin receivers.

  • The first is by turning off the radio receiver circuits for a few seconds between position updates so the unit only 'wakes up' and gets a new position every 5 seconds instead of every second.  
  • The second method is to stop listening for satellites that are low on the horizon and likely to be blocked by terrain. That way the unit can turn off some of the 12 receiver channels to save power.
  It only goes into Battery saver mode if your motion is reasonably predictable.  If the new position is considerably different to what the unit expected or if it fails to get a lock, then it reverts to continuous (once per second) updates until things become predictable.


The main downside of this mode of operation is that the unit is more susceptible to losing lock if it can't find the signals when it 'wakes up' or if the satellites high in the sky are blocked for some reason and it has stopped looking for the ones lower in the sky.


Test Results    ( using  Eneloop Pro 2800  NiMH batteries )
  • Battery saver mode with back lighting turned off  -  23.5 hours of  use.
  •  Battery saver mode with back lighting at 100% constantly on  -  10.25 hours of use.



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