The Alco-Sensor VXL instrument has the capacity to store a large number of tests in its memory. If a fresh set of batteries are installed in the instrument after the instrument has had no power for a short period of time, the Alco-Sensor VXL will re-initialize the memory database as a self-diagnostic process. During this process the instrument emits a constant beep to indicate that it is performing this task. The length of time to complete the process, and for the constant beep to stop, is dependent on the overall amount of data stored in the instrument. In software versions with a large amount of data stored this could take up to 5 minutes. Should the noise persist for more than 5 minutes, please contact Intoximeters Technical Services Department, or your local distributor, for additional support.