- When the instrument is set to:
- Wake up every 5 seconds
- Take a sample
- Go to sleep for a few seconds
- Wake up ... take more samples .. go to sleep
- etc
We have found some units will miss the scheduled wake up time, instead they wake up 24 hours later.
This only occurs:- In Timer Trigger mode.
- With the Log Period set to the minimum time ( 5 seconds).
- PowerDown after recording enabled.
CAUSE
The instrument uses a real time clock to schedule the wakeup time. Because of 3 second warm up time (minimum), and a 2 second "house keeping tasks" time - some units miss the scheduled wake up if the clock's second counter rolls over. This causes the next wakeup time to occur in 24 hours. This only happens for power down periods of less than 7 seconds.
SOLUTION
Do not enable PowerDown for log periods less than 10 seconds.
Note: There are two methods that allow you to gather data every 5 seconds:- Set the trigger to Manual Trigger.
- Set the sample period to 5 seconds.
or
- Set the trigger to Timer Trigger.
- Set the Sample Period to 1 second.
- Set "After Recording: Remain Awake".
No functionality is lost with these alternatives - which both avoid powering down for short times (ie offer no energy savings) In future releases, the minimum PowerDown time will be set to 10 seconds.
