Vicon surveyor X971, Installation And Operation Manual

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Alarms are electronic TTL (transistor-
transistor logic) type inputs that are driven
by a dry contact type switch. The switch
has two states, open and closed. For
example, in Figure 19, a door switch can
activate an alarm when connected to a Mini
Dome alarm input. These signals require
an unshielded twisted pair cable. As a
guideline (under normal conditions), the
cable should be 22 AWG for a 1000 foot
(305 m) distance The states correspond
to defined TTL designations as follows:
O
PEN = HIGH
Figure 19
Typical Alarm Circuit
CLOSED = LOW
where:
HIGH = 5 VDC
LOW = < 1 VDC
Since dry contact switches are normally defined in terms of their inactive or “normal” state, the following holds
true: NORMALLY CLOSED (NC) = ACTIVE HIGH (OPEN)
NORMALLY OPEN (NO) = ACTIVE LOW (CLOSED)
The “active” state can be programmed through the Mini Dome menu system. Alarm signals can be
programmed for their status (enabled/disabled), active level definition (high/low), action/reset function (none,
preset, aux on, aux off or tour), acknowledgement mode (automatic/manual) and report status (yes/no).
Auxiliary outputs are electronic open
collector type outputs which drive external
devices In Figure 20, a light can be turned
on and off when an auxiliary signal is
connected to a relay. Auxiliary signals can
be programmed for their active level
definition (high/low), power-on state
definition (on/off) and output type definition
(momentary or latching). For this example
the output must be defined as Active Low
(NO) and latching.
Each output can drive a relay at about 35
volts and 100 mA typical. There can be a
maximum of eight auxiliary outputs and
eight alarm inputs (twisted-pair sets).
Connect the DC voltage required for the
relay drive coil to TB3, pins 9 and 10. The
positive (+) side goes to pin 9, Common
and the negative (-) side goes to pin 10,
Ground. The relay drive IC will switch
negative connection (Ground) to the
appropriate output. In addition, the relay can be used as a set of dry contacts for a Normally Open device
input.
Figure 20
Typical Auxiliary Output
NOTE: For more information on auxiliary outputs refer to Vicon Technical Bulletin TB5156, “Application of
Open Collector Relay Outputs”.
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Wiring X971 Rev 1098 Surveyor Mini Dome System