General Directions For Installation - Videx ESVK Manual

ESVK/KRV86 - ESVK/KRV88 Series "2 wire Bus" videokit

General directions for installation

CABLE TYPES AND CROSS SECTIONAL AREAS
The ESVK two wire videokits with 7" monitors can use several types of cables but depending on their specification will allow differ-
ent distances up to 250 meters maximum. We do not recommend the use of shielded cables because of the high eddy capacitance.
It is also not advised to double up on cables as this will also increase the capacitance. The following table specifies values of resist-
ance, capacitance and maximum distances achievable for several types of cables (capacitance and resistance values are referring
to 100 metres of cable).
Cable Type* Wires Section
(mm2)
VIDEX CM2 0.50
CAT5 UTP/CW1308 0.22
Std Telephone Cable 0.28
Standard wire 0.5
* It is important that the video intercom system cables do not run with mains or other high power cables. Noise from such
cables (electromagnetic interference) may cause noises on audio/video and lost functionality. In cases where this advice
can not be followed or when existing cables are to be used it will be necessary to carry out tests to assess the quality and
functionality of the installation.
** This distance represents the maximum cable length from the outdoor unit to the farthest indoor unit. There are two impor-
tant characteristics to consider when calculating cable, the resistance and the capacitance. The resistance of the cable from
power supply to end point must be less than 10 Ohms and can be calculated from point to point. The capacitance of the cable
must not exceed 40nF and is an accumulation of all lengths and branches of the cable. For example: because of cable capaci-
tance, the Videx CM2 cable used in a single system cannot exceed the 400m considering all lengths and branches of the cable.
*** This distance represents the maximum total cable length from the power supply unit to the farthest indoor unit. With more than
one indoor unit, each sum of the cable segment from the outdoor unit to the power supply unit plus the cable segment from the
power supply unit to each videophone, cannot exceed the maximum mentioned in the fourth column of the table above.
In case of use of cables not in conformity with above specification it is possible to experience deterioration of digital and video signals.
We suggest to use twisted cables with maximum resistance of 10 Ohm (between the furthest door station and the furthest video-
phone) and maximum capacitance of 40nF (this value must be calculated considering all the cables used in the system; the capac-
itance/metres value is normally specified on the cable package or directly on the cable).
BUS DEVICE SETUP AND VIDEO DISTRIBUTION
• When changing dip switch settings, disconnect the device from the bus for a minimum of 1 minute to allow the unit to fully discharge.
• When you have more than one device in the same apartment, all the devices must be connected to the same video distributor
(Art. 317N): this means that you cannot use two video distributors Art. 318 for one apartment where you have 4 videophones/intercoms.
• After completing the installation proceed to testing. The video level gain can be adjusted at several points including distributors,
entrance exchanger and bus boosters.
HOW TO CONNECT A LOCAL POWER SUPPLY
The drawing below shows how to connect a local power supply when required (i.e. when you have 4 videophones with the same
address that must be switched on at the same time). In both cases switch 4 of SW3 must be set to the ON position.
NOTE! OBSERVE CONNECTION POLARITIES AS SHOWN IN THE DIAGRAM BELOW.
ON
Close
Open
1
Bus
Termination
ART.6788
Extension N. 2
Videophone: 1
ESVK/KRV86 - ESVK/KRV88 Series - Installation handbook
Resistance
(Ohm)
per 100 metres
3.2
8
6.5
2
+ -
12Vdc
ART.
323/12
230V
ON
2 3 4 5 6 7 8 1 2 3 4
Art.6788
Capacitance **Maximum Distance
(nF) between outdoor unit
per 100 metres and the farthest indoor
unit (metres)
8 250
4.9 100
5.5 150
6.5 70
- 6 -
***Maximum Distance
between power supply
and the farthest indoor
unit
100
50
50
30
Art.2321
BUS
Art.KRV782
Art.KRV782
Extension N. 3
Address: 1
66550045-EN - V6.2 - 31/10/20