Cables for video surveillance. Description and choice of use the best cables for video surveillance
The cable, as a passive element of the system, is still too often seen as secondary to the equipment. In fact, even modern broadcasting standards (e.g. HDCVI , AHD , HDTVI ), have been developed by the main manufacturing companies as attempts to allow the upgrade of analogue systems without the need to replace cables, or to allow the use of new high-definition cameras with special protocols capable of being transmitted over coaxial cables, reusing the cables laid for the old analogue systems, and promising great results even with poor quality cables.
It was soon realized that by installing the new HD cameras on the old RG59 or similar cables, it only works well with short sections of a few tens of meters, because they have passed 5 MHz band (typical of analogue) to the current one up to 150 MHz (typical of HDCVI 4K ). The continuous evolution of video tools and standards, with ever higher quality and definitions, have also made it necessary to develop equally performing cables. This has led to the birth and continuous implementation of our VS / VSHD series, specifically designed to support the most advanced analog and digital (or hybrid) shooting and transmission systems. , with high standards in terms of performance and whatever the protocol or image resolution used ( HDCVI , AHD , HDTVI ).
Differences and characteristics of video surveillance cables
As an example, all cables provided by Cavel ® , whether they are network or coaxial, they are also available in combined format (signal + power supply), i.e. supplied with power cables of different sections, which make installation possible with a single laying.
The world of video surveillance is divided into:
- HDCVI , AHD , TVI and ANALOG coaxial cameras (the latter no longer in use);
- IP (Internet Protocol) cameras.
For coaxial cameras, Cavel ® has developed 4 coaxial cables in LSZH that allow routes of hundreds of meters:
- VSHD40 (3.6 mm microcoaxial) for sections up to 250 m ;
- VSHD70 for routes up to 400 m ;
- VSHD80 for routes up to 500 m ;
- VSHD113 for routes up to 700 m ;
(the above sections refer to use with HDCVI 4K cameras). Of the cables listed above, Cavel ® also produced the combined version with power cables (red and black) of 0,5 , 0,75 and 1 mm² of section, for separate power supply of the coaxial camera.
For IP cameras , which use Ethernet output, Cavel ® has developed a Cat.5e cable called VS540 in LSZH both in LAN-only format (for powering the camera according to the PoE Power over Ethernet standard), and in a combined format with power cables (red and black) from 0.5 0.75 and 1 mm² section, for devices with separate power supply.
On the site www.cavel.it , in the section TECHNICAL SUPPORT / CALCULATION - DROP it is possible to calculate the voltage drop of the system by entering the type of cable, the current absorbed by the camera and its length, to best size the power supply system. The same calculation can be made considering the loop resistance (outward + return) indicated for each cable in the relative section on catalog .
LSZH sheaths only: technical properties and laying suggestions
An important feature, common to all cables Cavel ® dedicated to Video surveillance, including electrical conductors, is to be provided with a halogen-free sheath that exhibits the following properties:
- Non-propagation of flame and fire.
- Low smoke emissions.
- Absence of halogen fumes.
- Resistance to UV rays.
- Ideal for internal and external installation and in underground cable ducts.
- Recommended for installation in public places and in all cases of safety need in case of fire, such as: schools, hospitals, banks, airports, etc.
- A Standard CEI-UNEL 36762 , which allows the laying of the power cables in the same distribution ducts.
Physical characteristics of the cables
Installation temperatures: -0 to 50 ° C
- PVC sheath - 30 to 80 ° C
- LSZH sheath - 25 to 80 ° C
- PE sheath - 40 to 80 ° C
Below is a summary table of tests carried out by us:
|CABLE TYPE||CAMERA TYPE|
| MAX LENGTH
||MAX TRACTION FORCE (*)|| HDCVI 4K
(8 Mpixel = 3840 x 2160)
| AHD 2K
(4 Mpixel = 2560 x 1440)
| TVI 2K
(4 Mpixel = 2560 x 1440)
(*) Remember that the thinner the cable, the more delicate it is; therefore care must be taken during installation, to the maximum traction force indicated in the table.