Vicon SurveyorVFT Series, Инструкция по установке и эксплуатации

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Reference
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
eferred dielectric material is cellular (foam)
but is more vulnerable to moisture. Therefore,
to moisture. The shield
Cab
The RG-59/U and RG-11/U. Each is actually a family of cables with widely varying
cha
betw
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
Recommended Coaxial Cable Types
Typ Type No. Type No.
Type
Conductor
% Coverage
DC
ohms per
1000 feet
(km)
normal use, select a cable with a stranded center conductor. The pr
polyethylene. It has better electrical characteristics than solid polyethylene,
use only solid polyethylene dielectric cable with a heavy exterior insulation in applications subject
must be copper braid providing 95% or better coverage.
le Types
most commonly used cable types are
electrical characteristics, some of which are not suitable for CCTV applications. Choose a cable type by referring to the
racteristics and maximum distances listed below. The maximum distance for best picture refers to the distance
een
copper and “TC” refers to tinned copper.
Cable
e
Belden
Type No.
Alpha West Penn Center
Type Shield and
Resistance
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
)
7.5 (24.6)
braid (100%
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.
1.5-inch Pipe Designation
The standard “1.5-inch pipe” referred to in this manual has actual dimensions of:
Outside diameter: 1.9 inches (48.3 mm).
Inside diameter: 1.61 inches (40.9 mm).
Wall thickness: 0.145 inches (3.37 mm) minimum (ANSI “standard” grade thickness).
XX152-02-00 Rev 1004 SurveyorVFT Fixed Camera Dome Reference
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