User Manual

Operation 4-17
Light Curtain
The Light Curtain is an optional substitute for transparent front doors, and it operates
according to the same rules. To detect obstructions the Curtain uses an emitter and a
receiver. The emitter has a vertical array of infrared lights which shine upon the receiver’s
matching array of light sensors (Figure 4-5). The emitter and receiver are mounted vertically
on either side of the dispenser’s front entrance. When an object 19mm (0.75 in) in diameter
or larger interrupts the invisible light beam between an emitter/receiver pair, the blockage
triggers the Safety Interlock system. The Interlock System then disables the dispensing
machinery, but leaves the computer system on.
If the machine currently is not running a dispensing program, an intruding object will cause
a recoverable interlock condition. In this case, the yellow light in the
DISPENSER STATUS
section of the Control Panel turns ON (Table 4-6) and the yellow light on the Light Beacon
turns ON. To recover, simply remove the object. The system will resume normal status.
If the machine is actively running a dispensing program, an intruding object will cause a
non-recoverable interlock condition. In this case, the red
ABORT light on the Control Panel
turns ON. The red light on the Light Beacon also turns ON (Lights on the Control Panel and
the Light Beacon will always have the same color). To recover, remove the object, press
SYSTEM RESET, and press FIND HOME on the Control Panel. See Table 4-6 for
INTERLOCK rules.
Figure 4-5 Light Curtain
Receiver
Emitte
r
Close-ups of
Light Curtain Indicators