JVC SW-D8000U Instruction Manual page 61

SW-D8000U, 16CH. COLOR VIDEO MULTIPLEXER
When setting sensitivity, choose the highest setting that does not result in very frequent 'false'
motion detections. The higher the sensitivity, the more likely it is that incidental movement will be
detected as motion, so if motion is indicated without apparent cause, reduce the sensitivity.
When setting high sensitivity, such as 8, 9 or 10, it is important to ensure that sources of false
motion, such as trees and bushes which may move in the wind, or windows which can reflect
flashes of light, are eliminated from detection if possible. To do this, DISABLE the corresponding
zones as described above in SETUP ACTIVE ZONES.
Sensitivity Scope:
Refer to the description under SETUP ACTIVE ZONES sub-menu for further information on setting
sensitivity.
Record Rate: (This setting is only used in ACTIVITY DETECTION).
Your multiplexer shares one VCR between many cameras.
which normally provides 60 fields a second must be time sliced and reduced to a rate of far fewer
fields every second to allow the other cameras to insert fields into the same video stream going to
the VCR. (Refer to the explanatory figure in the RECORDING section of this manual.)
The lowered update rate for each camera is not a problem if there is little movement in the scene,
but if there is activity in the camera view it is always preferable to get as many updated fields of the
activity as possible so that important activity events are recorded.
The SW-D8000U solves this dilemma in two ways:
1. It has a very fast, optimized update rate to tape, which at 2-hour alarm speeds is about 3
times faster than most other multiplexers.
2. It allows the rate of update of each camera to tape to be automatically adjusted by the
system if there is ongoing motion within a camera's field of view. In this way, cameras
without activity are recorded less often and cameras with frequent and continuous activity
are recorded more often and so can capture more of the activity.
A unique feature of the SW-D8000U is that the increase in update rate can be set by the
programmer in this RECORD RATE sub-menu. Cameras with activity can be recorded twice (2X)
as often they would normally be recorded, or four times (4X) as often, or they can be
INTERLEAVED. This allows programmers the flexibility to set up the system according to the
requirements of their particular installation.
NOTE: The record list and record rate can also be modified by an active alarm. A record list
update resulting from an active alarm input will always override any record list
modifications which resulted from sensing activity. (See ALARMS sub-menu RECORD
MODE)
There are four choices of RECORD RATE for activity:
q NONE - If most cameras are expected to have motion at the same time, or if the particular
camera scene is not important yet has a lot of motion.
q 2X - If not all cameras are connected.
q 4X - The factory default setting.
q INTERLEAVED - If very few cameras will have motion at any one time.
Relay Output:
Two relay outputs are provided to enable the programmer to program automatic external actions
such as a speed change on the VCR, or floodlights, or audio announcements and so on. The relay
JVC PROFESSIONAL, IMAGING PRODUCTS
As a result, the video from a camera
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