Consilium SRT, Техническое руководство

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SRT X-BAND RADAR SYSTEMS
FUNCTIONAL DESCRIPTION
304202P003 3.13 Rev. C
Speed controller board sets brushless motor rotation speed by means of vari-
able voltage signal VEL coming from SRT_Control Board. An enable control 5V
signal is produced as well (start), for safety purpose. Turning the safety switch
off results in preventing motor from rotating (Chapter 9, Figure 9.1.26).
3.2.4
Motor Unit
The Motor Unit, on which 6' and 9' and 12 ´X-Band Antennas can be mounted,
is equipped with an Electric Motor powered by the Brushless Motor Controller
board in the casting
(Chapter 9, Figure 9.1.5).
The motion is transferred to the X-BAND ANTENNA through 2 GEAR
REDUCTION GROUPS, with a total reduction ratio of 60:1.Note only for 6 and 9
feet per 12 feet is 120:1. The ANTENNA nominal angular speed can be
≥ 40
rpm.
On the Antenna shaft is mounted the OPTICAL READ-OUT group that
generates the pulses used to determine the Antenna position (Azimuth) and the
Heading Line.
The OPTICAL READ-OUT group is composed of a disk rotating with the
Antenna shaft and an optical sensor composed of two slotted optical switches.
When in front of the optical sensor passes a hole of the disk, a pulse is
generated by the Photo-transistor. The pulse is sent to the INTERFACE block of
the Electronics Rack through the SIGNAL CONDITIONER circuit, which adapts
the amplitude of the pulses from the Optical Read-out
The Heading Line pulses are obtained by means of another optical sensor,
equal to the previous one, which generates a pulse when a deeper hole passes
through the sensor.
On the SRT_Control board, it is applied a SAFETY SWITCH. This switch
positioned outside the equipment, when open, disables, in the SRT, the power
supply for the MOTOR and inhibits RF emission, thus achieving a safety
condition when personnel have to operate on the equipment both for
maintenance and for repairing. The wiring from the switch enters in the
equipment through the smaller stuffing tube. The installation is compulsory and
it is recommended to install the switch at the bottom of the mast stairs giving
access to the Unit.
NOTE
Before performing any service on the Antenna, SWITCH OFF
the Safety Switch.