18
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Reference
XX150-06-00 Rev 1010 Roughneck V926 Fixed-Position Camera Dome
Reference
Coaxial Cable
Coaxial cables used to route video signals to and from the unit must meet the video recommendations in this section.
Caution: Careful selection of the proper cable is essential to obtain the best performance from this
equipment. Vicon assumes no responsibility for poor performance when cables other than those
recommended are installed. In all cases, coaxial cable impedance should be 75 ohms.
Materials
Use only cable with a pure copper center conductor. Do not use cable with either a copper-plated steel or an aluminum
center conductor because these do not transfer signals effectively in the frequency range used in CCTV networks. A
center conductor with low DC resistance is required for effective CCTV operation. Solid-core bare copper conductor is
best suited to video applications, except where flexing occurs. If the coaxial cable will be subjected to flexing during
normal use, select a cable with a stranded center conductor. The preferred dielectric material is cellular (foam)
polyethylene. It has better electrical characteristics than solid polyethylene, but is more vulnerable to moisture. Therefore,
use only solid polyethylene dielectric cable with a heavy exterior insulation in applications subject to moisture. The shield
must be copper braid providing 95% or better coverage.
Cable Types
The most commonly used cable types are RG-59/U and RG-11/U. Each is actually a family of cables with widely varying
electrical characteristics, some of which are not suitable for CCTV applications. Choose a cable type by referring to the
characteristics and maximum distances listed below. The maximum distance for best picture refers to the distance
between the camera and the unit. The characteristics of the cables in this table should be used as a guideline when
cables other than Belden are used. Materials and construction must follow the guidelines above. Note that “BC” refers to
bare copper and “TC” refers to tinned copper.
Recommended Coaxial Cable Types
Cable
Type
Belden
Type No.
Alpha
Type No.
West Penn
Type No.
Type
Center
Conductor
Type Shield and
% Coverage
DC
Resistance
ohms per
1000 feet
(km)
RG-11/U** 8213
9847
811,4811
14
Solid
BC
BC braid (95%)
2.6 (8.5)
RG-6/U
9248
9804C
806,4806
18 Solid BC
Foil + 61% TC
braid (100%)
7.5 (24.6)
RG-59/U
8281
9803
815
20 Solid BC
2 TC braids (96%)
9.9 (32.5)
RG-59/U 9259
----
816
22
Stranded
BC
BC braid (95%)
15.0 (49)
RG-59/U 9659
----
----
22
Stranded
BC
BC braid (95%)
15.0 (49)
Picture Quality vs. Cable Length
Picture Quality
Maximum
Cable Run*
ft (m)
RG-59/U
RG-6/U
RG-11/U**
Usable picture
1100 (350)
1500 (450)
2400 (750)
Clean picture
820 (250)
1000 (300)
1600 (500)
Best picture
400 (120)
530 (160)
820 (250)
* For longer cable runs, refer to the Product Specifications for Video Amplifiers.
**RG11 cable is too thick to be routed to the V926; it must be pigtailed down to a usable size to be used
in an installation.
Summary of Contents for Roughneck V926-C26
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