SIGMA projetor - Manual (Page 26)

DAILY INSPECTION INSTRUCTIONS
3.4
Transit Mode
Rotating the handle of the remote control crank in the EXPOSE direction (counter-clockwise) moves the
source assembly out of the shielded position in the exposure device and into the source guide tubes
(projection sheaths). (See figure 3.3)
The source assembly is under positive mechanical control using the remote control crank. The remote
controls may be fitted with an odometer to provide an indication of the sealed source’s position. The
odometer reading should never be a substitute for the requirement and proper use of a radiation survey
meter.
Figure 3.3 Sealed source in transit mode
Exposure Mode
When the source assembly reaches the exposure head at the radiographic working position, the
odometer will indicate (in feet and tenths of a foot) the approximate distance the sealed source has
traveled. (See figure 3.4)
To return the source assembly to the exposure device the crank handle is rotated in the
RETRACT direction (clockwise). When the source assembly is returned to the fully shielded position
within the exposure device, the locking mechanism automatically secures the source assembly. The
automatic securing mechanism will not permit exposure of the source assembly unless the radiographer
pushes the lock slide into the expose position.
The remote controls cannot be disconnected from the source assembly unless the source assembly is
fully retracted into the shielded position in the exposure device.
The system is designed for safe and reliable operation provided the system is properly used and
maintained.
Control Cable Exposure Device
Source Assembly
Sealed Source
Remote
Control Crank
Locking
Mechanism
Shield Outlet Port Source Guide
Tubes