PLANET HDVR-1630 - Manual (Page 76)

Hybrid Digital Video Recorder
HDVR series
76
When a channel is added to device but it is not enabled, you will see as shown below.
Channel status interface in full digital (NVR) mode (One of the channel is without device.)
When the current resolution is over the max resolution that the channel
supports, then a red “X” will be shown on the preview image. For example,
in full digital channel mode, the maximum resolution of channel is D1. If the
HDVR connects to a camera with resolution over D1 (such as 960H), you
will see the picture shown below.