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SM42A / SM82A 2802
4.1.2 Manual selection
From the keyboard, the operator can directly select a desired input, interrupting the automatic switching sequence.
A specific input video is always selected with reference to the active monitor: if the keyboard is authorised to
control more than one monitor only the “active monitor” (the last one to be selected) will be involved in the input
video selection.
The local keyboard and the remote DCTEL and DCBD keyboards can be used to control all outputs. Keyboards
DCJ and DCK can be configured to restrict access to a set of output videos dedicated to each operator, so as to
prevent unauthorised personnel from operating at will on all outputs.
4.1.3 Using the Inc/Dec keys
The Inc/Dec keys can be used to block an automatic switching sequence on one input and, where appropriate, to
select the next/previous input video (following the preset order for the switching sequence in progress) without
having to use the numeric keypad to select an input.
4.1.4 Output video dedicated to the VCR
Output video n°2 of matrices SM42A and SM82A is dedicated to the VCR if it is enabled. In this case control of the
VCR channel is only subject to the trigger impulse itself. Any command that may be sent from the keyboard
concerning this channel will therefore be ignored.
4.2 Alarms
The matrix provides a DB15 alarm connector, to which 4/8 (depending on the SM42A / SM82A model)
alarm contacts ("alarm input") can be attached, one for each of the input videos of the video device.
When an alarm is activated:
•
the keyboards able to display the alarm condition can activate a warning buzzer and may also show the alarm
status with a screen message or a flashing LED (this type of operation is determined by the characteristics and
configuration of the individual keyboard).
•
each output that is enabled for recognition shows the video signal corresponding to the latest recognised alarm
in order of time; if an output is not enabled for recognition of the alarm condition, the alarm will not be shown on
the video
•
the alarm relay will be closed (auxiliary contact) and in some cases a warning buzzer is activated inside the
matrix, if this is allowed for, by the alarm contact configuration
•
the text identifying the corresponding input is accompanied by the word “ALARM”.
Alarm status will be stored internally and will be kept, even if there is a temporary interruption to the matrix power
supply.
Warning! The alarms must be configured with special care, because a mistake in their settings could cause
faults in operation that are difficult to identify.
4.2.1 Alarm contact types
Each individual alarm contact can be defined:
•
normally open (N.O.): the alarm condition is recognised when the alarm contact is short circuited to the
common alarm pin
•
normally closed (N.C.): the alarm condition is recognised when there is a break in the contact between the
alarm and common alarm pin
•
not used: the alarm contact is ignored.
Warning! Pins that are not connected to any alarm contact should be configured as NOT USED.