Once the Contro-3 has scanned a box and determined that it is either okay or isn’t, that box cannot be check weighed again until a different box has been scanned. This guards against unintentional duplicate scans. If you try to scan a box twice the scanner will beep, but the Contro-3 will ignore the scan.

• NOTE: If you are unsure whether you have already scanned a particular box it is always okay to check weigh it again. The PC will spot and remove and duplicate serial numbers, so that only one record will get added to inventory.