1. Check if the DVR power Led is on. 2. Connect the power supply to a different surge protector and different power outlet. 3. Change the power supply of camera to test. 4. Test power supply with Volt meter.
1. Please kindly read user manual or watch the video on the website firstly to know how to upgrade the DVR. 2. Please copy upgrade file named”rootfs-hi3520d”directly to your USB-drive Note: you can get the same model upgrade file from our company website download center, or contact with our service to get it. 3. After upgraded, Please go to the DVR Main menu–information– System to check if the firmware version is the latest or not , if yes, that means upgrade successfully.
1. The power supply is not correct. 2. Incorrect power connection. 3. Power supply is defective. 4. A program error has occurred . 5. The hard disk is damaged or something is wrong with the hard disk cables 6. The control panel is damaged. 7. The main board of the DVR is damaged.
1. The input voltage is not stable or too low. 2. The hard disk is damaged or the hard disk cables are broken. 3 The power supply is faulty. 4. The front-end video signal is not stable. 5. Poor heat dissipation, too much dust, bad running environment for the DVR. 6. Something is wrong with the hardware of the DVR .
1. Something is wrong with the data cable or the jumper of the hard disk 2. The hard disk is damaged or no video data. 3. Upgraded software has been installed which is not compatible. 4. The video files you want to see are overwritten.
1. The video quality is set too low. 2. The program data reads wrongly, may be restored after rebooting the DVR. 3. Something is wrong with the data cable or the jumper of the hard disk. 4. The hard disk is damaged. 5. The hardware of the DVR is damaged.