Alcad PDK-41500 Mode D'emploi page 33

In estate installations, making a call from one of the external entrance
panels does not disable the entrance panels of the building which is being
called.
Check connections D2 and D3 from the entrance panel to the identifying
accessories of the building. If the fault cannot be found, there may be something
wrong with the audio unit or the identifying accessory.
The video system does not work in any monitor: auto switch-on, screen
doesn´t come on when receiving a call,..
Check the mains voltage in the power supply unit that feeds the monitors.
Check that the voltage of the power supplies between - and + is 15 ±
10% Vdc. Check if there's a short circuit and rectify it. Disconnect the
power supplies supply for 1 minute and reconnect it. If the breakdown
continues, disconnect all the - and + terminals from the power supply unit
and check that voltage between - and + is 15 ± 10% Vdc. Check the
conexion between the power supply and the audio unit. If it's not correct,
there may be something wrong with the power supply.
The video system does not work in any monitor: auto switch-on, screen
doesn´t come on when receiving a call,..
Check the mains voltage in the power supply unit that feeds the monitors.
Check that the voltage of the power supplies between - and + is 15 ±
10% Vdc. Check if there's a short circuit and rectify it. Disconnect the
power supplies supply for 1 minute and reconnect it. If the breakdown
continues, disconnect all the - and + terminals from the power supply unit
and check that voltage between - and + is 15 ± 10% Vdc. Check the
conexion between the power supply and the audio unit. If it's not correct,
there may be something wrong with the power supply.
Video system does not work in one monitor: auto switch-on, screen doesn´t
come on when receiving a call,..
Check that the ON/OFF switch for the video is in ON position (on the
left). Check that the red led of the monitor is on. Check the connection
between the connection bracket and the monitor. Check that the voltage
between - and + of the connection bracket is 14 ± 10% Vdc. If failure
cannot be found, there may be something wrong with the monitor.
Poor image quality on all the monitors: distorted picture, ghost images,
loss of synchronisation.
In multiple access installation, check that you have only one entrance
panel defined as the main one.
If splitters have been used in the distribution, check that the voltage between
- and + of the splitters is 15 ± 10% Vdc.
Check that coaxial cable line has a 75 Ohm load: a) if tap-offs have been
connected in series the 75 Ohm resistance must be removed from all the
intermediate tap-offs; b) with monitors in series cut the 75 Ohm resistances
on all the connection brackets, but from the one at the end of the line; c)
DIGITAL DOOR ENTRY SYSTEMS
Poor image quality on one monitor: distorted picture, ghost images, loss
of synchronisation.
Auto switch-on does not work on any monitor.
Auto switch-on does not work on one monitor.
Blank screen on all the monitors
Blank screen on all the monitors of a flat.
Blank screen on one of the monitors of a house or flat.
.
Check coaxial connection in splitters and tap-offs. If you cannot find the
fault, there may be something wrong with the video unit. Check that
resistences of 75 ohms are connected in the unused terminals V2, M.
Check that coaxial cable line is charged with 75 Ohm: with monitors in
series cut the 75 Ohm resistances on all the connection brackets, but from
the one at the end of the line. If you cannot find the fault there may be
something wrong with the monitor.
In multiple access installations, check that one entrance panel has been
defined as the main one and check connections D2 and D3 between
different entrance panels. If you cannot find the fault there may be
something wrong with the audio unit.
Check that pushing the auto switch-on button the red led flash. Check
that the system is not engaged. If you cannot find the fault, there may be
something wrong with the connection bracket or the monitor.
Check the connection between the video and the audio units. Check that
the coaxial cable to the monitors is connected to the V1 and M terminals
of the video unit. If this is the case, check connections V2, M and V4, M
of the video units of the installation. If splitters have been used in the
distribution, check that the voltage between - and + of the splitters is 14
± 15% Vdc. Check the connections of the coaxial cable from the video
unit to the monitors. If failure is not detected, there may be something
wrong with the audio unit, video unit or any splitter.
Check the position of the J1 configuration jumper in the connection
bracket. Check coaxial's connection from the connection bracket to the
video unit. If splitters have been used in the distribution, check that the
voltage between - and + of the splitters is 14 Vdc ± 15%. If the fault
cannot be found, there may be something wrong with the tap-off of that
floor or the splitter of he flat.
Check the connection between the connection bracket and the monitor.
Check the connections of the coaxial cable in the monitor's connection
bracket. f splitters have been used in the distribution, check the position
of the J1 configuration jumper in the connection bracket. Check coaxial's
connection from the connection bracket to the video unit. If failure is not
detected there may be something wrong with the tap-off, connection
bracket or monitor.