Vicon VC2430B, Руководство по установке и эксплуатации

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Coaxial Cable Recommendations
Caution: Careful selection of 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, or equivalent, are installed. In all cases, coaxial cable
impedance should be 75 ohms.
Materials
Use only a pure copper center conductor. Do not use a copper-plated steel or aluminum center conductor, as they will
result in poor quality video. Solid-core bare copper conductor is the best type, where flexing and bending will be minimal.
If severe bending and flexing is required for installation, use a stranded center conductor. Never exceed the
manufacturer’s minimum bend radius specification. Use cellular (foam) polyethylene dielectric except where heavy
moisture exists. For moisture conditions, use solid polyethylene dielectric cable with a heavy exterior insulation. The
shield must be copper braid providing 95% or better coverage.
Cable Types
The cable types listed below are the most common 75-ohm types used. They vary in size (diameter), dielectric type and
net DC resistance. The larger cable results in a lower DC resistance and better video quality, with increased difficulty in
handling and installation. Let the required picture quality and cable distance provide a guide in choosing the best cable
type. For cables other than the approved Vicon types below, contact the manufacturers listed below. 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/1000 ft (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* ---- 815 20 Solid BC 2 TC braids (96%) 9.9 (32.5)
RG-59/U 9259 9803 816 22 Stranded BC BC braid (95%) 15.0 (49)
RG-59/U 9659 ---- ---- 22 Stranded BC BC braid (95%) 15.0 (49)
*Requires special BNC-M connector due to 0.305 nominal O.D.
Belden
Inc. http://www.belden.com/ (800) 235-3361
Alpha Wire Company http://www.alphawire.com/ (800)-52 ALPHA (522-5742)
West Penn Wire http://www.westpenn-cdt.com/ (800)-245-4964
Picture Quality vs. Cable Length
Maximum Cable Run** ft (m) Picture Quality
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, use a Vicon Video Amplifier to obtain a suitable picture.