7
small time constant by pressing the button «AGC» (automatic gain control) on Rx.
In this case an express setup of the amplifier takes place in the standby state.
5.2.5.
On the Rx unit the blocking button is placed
in order to prevent unauthorized
openings of the back panel. In the operating condition the blocking contacts are
closed, at the back panel opening they are broken. The alarm cables circuits
marked «TAMPER»; «TAMPER» are broken too.
5.3.
Sensor operation
5.3.1
. The preparation to the sensor operation is the following:
- preparation of the sector;
- signal cables and power supply laying;
- Tx and Rx installation;
- sensor connection (connection of power supply and intruder alarm loops);
- alignment of Tx and Rx antennas
- setup of Rx thresholds.
The principles and methods of these steps are given in the items 8-10.
5.3.2.
The sensor has the following operating regimes:
- standby state (closed relay contacts)
- alarm signal (open relay contacts)
- blocking state of Rx (open blocking contacts).
5.3.3.
The receiving and control device realizes the receipt and indication of alarms. The
sensor operates with the receiving-control devices, which control relay contacts.
5.3.4.
Periodically the remote control device checks the sensor efficiency.
The constant voltage from 5 up to 30 V is biased for 1…3 sec on the Tx wire
marked «RC». The beaming of Tx is interrupted for the time and then Rx generates
an alarm.
The alarm generation after the «RC» signal confirms the sensor
operation and operability of the loop.
The control frequency is assigned by the
user.
5.3.5.
Besides there it is necessary to check periodically the technical state of the sensor
and its servicing. Recommended frequency of the checks is given in the item 11.
5.3.6.
The sensor power supply is provided by the power supply unit «PSU-U-24-0,7» or
by any other direct voltage source, satisfying the technical characteristics.
5.3.7.
Input circuits Tx and Rx are protected from short-term overvoltage (with the
amplitude up to 900 V), provoked by electromagnetic pulses (lightning discharges,
switching interferences and etc.). Nevertheless it is necessary to apply the lightning
guard unit «PSU-U-24-0,7» or similar units on the objects with high frequency of
thunderstorms.
Summary of Contents for FORTEZA-300
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