The R Series defibrillators perform a clock-synchronization FOLLOWING their scheduled automatic readiness test. The workflow is as follows:

1. The R Series defibrillator begins its automatic readiness test at the scheduled hour
   1. We usually recommend setting this to occur at 2am*
2. The R Series Defibrillator finishes its self-test a few minutes later and transmits the results to the Data Exchange Service server (DXS – either hosted by your hospital in-premise, or by ZOLL Online)
3. The DXS server responds with confirmation of receipt, and provides the CURRENT timestamp
4. The R Series Defibrillator receives that confirmation and timestamp and matches ITS clock to the time received from the DXS server

For DefibDashboard/DeviceDashboard users, because the defibrillator corrects its time AFTER performing the overnight readiness test then you may see that the defibrillator has an "incorrect" time through the dashboard should you view it later that same day when the DST changes occur. Once the defibrillator checks in again during its next 30 Joule test you should see the correct time is now being reported. For DeviceDashboard this would be the "Check Device Time" alert. Should your defibrillator still be reporting the incorrect time more than 48hrs after the DST change should have occurred, please contact Code Data Support for troubleshooting assistance.

*Daylight savings time changes occur at 2am, so by setting the automatic readiness test to occur at that same time then the defibrillators will correct their clock to match the new DST time only a few minutes after the time change occurred. This minimizes the amount of time that the R Series has an incorrect time clock. HOWEVER – if your organization is utilizing an in-premise DXS server and has a significant number of defibrillators (over 200), then having all defibrillators checking in at the same time can overburden a single server and result in R Series defibrillators timing out while waiting for the server response and the clock-sync not occurring. Follow the advice of your Data Deployment Engineer or contact ZOLL Code Data Support should you have questions about the best practice for staggering your defibrillator's check-in times for larger in-premise systems.