25H/SP/DDA/2W - TECHNICAL MANUAL
EN-UK - V.1.2 - 04/01/16
37
VIDEX
25H/SP/DDA/2W
(1 way “2 wire” DDA audio intercom kit)
Symptom
Tests / Checks to carry out
Intercom panel display
switches between ‘ERROR’
and ‘PRESS BUTTON
TO CALL’ and makes an
acoustic signal every few
seconds.
Check the polarity of the L/- BUS connections between the Art.138 speaker
and the Art.3171 audiophone.
Check the L/- BUS voltage (
should be 7.5Vdc at the intercom panel and at the
audiophone).
If necessary reset the Art.138N speaker as a ‘MASTER’ panel
(refer to dip-switch
settings on page 8).
When the call button is
pressed the intercom
panel is not able to ring
the
audiophone.
The
busy LED on the panel
comes ON and makes an
acoustic signal of ‘line
engaged’, but the display
shows ‘ERROR’.
Check the L/- BUS connections are terminated properly.
Increase the CSA of the L/- BUS connection by doubling up on the cable cores.
Check that the Art.3171 audiophone phone ID is correctly set as phone ID.1
(refer to phone ID dip switch setting on page 13).
Check that the yellow and white wires from the Art.138N speaker wiring
harness are connected correctly to the DDA call button
(refer to page 8).
The Intercom panel
makes a call correctly and
the audiophone rings,
but when answered the
communication is cut
OFF.
Check the L/- BUS voltage (
should be 7.5Vdc at the intercom panel and at the
audiophone).
Increase the CSA of the L/- BUS connection by doubling up on the cable cores.
The call rings through
to the audiophone okay,
but there is only one-way
speech.
Check the input voltage to the Art.138N speaker hasn’t dropped below 10.5Vdc.
Check the GND and +12Vdc connections on the Art.521 PSU and on panel the
Art.138N speaker, also check the voltage output on the PSU with and without
load.
The audio level of the
conversation is low.
Check both microphone and speaker POTs on the Art.138N speaker
(refer to
page 9)
and adjust in conjunction with the balance POT if necessary.
No lock release from the
audiophone.
Check that the ‘OPEN’ LED comes ON on the intercom door panel.
Check continuity of the relay contacts on the Art.138N when the lock button
on the audiophone is pressed.
Check the lock connections between the relay on the Art.138N and the lock
release.
Check for voltage on the terminals of the lock
(for fail secure locks 12Vdc should
appear across the lock terminals, for fail safe locks 12Vdc should drop off the lock
terminals).
