Vicon kollector KOL-8000, Руководство по эксплуатации

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Reference
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.
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 Receiver and the
Transmitter. The characteristics of the cables in this table should be used as a guideline
when cables other then Belden are used. Materials and construction must follow the
guidelines above. Note that “BC” refers to bare copper and “TC” refers to tinned copper.
Table A
Recommended Coaxial Cable Types
Cable
Type
Belden
Type
No.
Alpha
Type
No.
West Penn
Type No.
Type
Center
Conductor
Type Shield and
% Coverage
DCR/
1000 ft
(km)
Distance
(max)
ft (m)
RG-11/U 8213 9847 811,4811 14 Solid BC BC braid (95%) 2.6 (8.5) 820 (250)
RG-6/U 9248 9804C 806,4806 18 Solid BC Foil + 61% TC
braid (100%)
7.5 (24.6) 530 (160)
RG-59/U 8281 9803 815 20 Solid BC 2 TC braids
(96%)
9.9 (32.5) 400 (120)
RG-59/U 9259 ---- 816 22 Strand
BC
BC braid (95%) 15.0 (49) 400 (120)
RG-59/U 9659 ---- ---- 22 Strand BC braid (95%) 15.0 (49) 400 (120)