Videotec SM84A Manuel D'instructions page 51

3.5.3 Connection s for alarm management
See pin configuration table for the DB25 connector.
3.5.3.1 Alarm contac ts
WARNING! Do not energise the alarm contacts! The sensors (or the alarm system in use) should supply
a dry contact. To manage the alarms correctly, be very careful when configuring the alarm parameters at the
matrix programming stage.
3.5.3.2 Auxiliary con tact (alarm relay)
The SM84A / SM164A matrix can be used to control an auxiliary contact (relay) that is activated when there is
an alarm, if properly configured at the matrix programming stage. The auxiliary relay contacts are at pins 21 and
22 of the DB25 connector.
3.5.3.3 External rese t
The reset impulse is recognised on the falling or rising edge (which can be set at the matrix programming
stage).
Pin 17 of the DB25 connector is associated with External Reset of the alarm condition and the ground reference
is pin 18.
3.5.4 Connecting the matrix to the peripherals
3.5.4.1 Control keybo ards (Keyboard lines)
All the keyboards specified in section 2.2 Connectable devices and the SM84A / SM164A video matrix can be
connected by telephone cable using the 4 RJ-11 sockets called KEYBOARDS.
They can be connected directly using the 1.5m cable (supplied with the control keyboards) for short distances,
or, for longer distances, using the RJ-jack wall-mounted boxes (supplied with the control keyboards).
This is not applicable to the previous series keyboards, which require a communication interface because they
do not have RS485 (except for the DCS3 model).
Moreover, the DCTEL and DCBD and Linxs series keyboards can be powered directly by the matrix.
All the keyboards should have transmission rate settings that are compatible with the settings made for the
matrix at the programming stage. See the respective manuals for the keyboard setup.
Summary:
TYPE OF KEYBOARD
DCJ, DCK, DCTEL, DCBD, DCT,
DCIR
LXRPK12, LXRPK23, LXRPRC36
DCMT8, SWC4, SWC8, SWC16,
DCS2, KEYPLUS
DCS3
(1)
Only keyboards DCTEL, DCBD
CONNECTION
Direct:
RS485
Direct:
RS485 and Power supply
Connection interface:
RS485 – CURRENT LOOP
Direct:
RS485
Page 11
MAXIMUM DISTANCE
RS485
Power supply
RS485
Power supply
CURRENT LOOP
RS485
MNVCSM84A_0408
1200m
(1)
700m
1200m
700m
1500m
1200m