4.10.2. Overhang Monitoring With External Sensors - Cedes ObjectC 100 I/O Programmer's Manual

Programmer's Guide
Figure 20: Example Overhang back side
▪ At least one of the carrier zone beams has to detect the carrier at all time during transit through
Note:
the light curtain. Special attention needs to be paid to carriers with openings, e.g. pallets.
▪ ObjectC 100 I/O: DIP switch S1 (7) has to be turned "OFF" (= 0)
▪ Output logic can be inverted (see chapter 2.2.5.11), default = active "Low"

4.10.2. Overhang monitoring with external sensors

A second way to monitor an overhang is by using a front and a back sensor, mounted in the carrier zone "zc"
(Figure 17). The amount of overhang allowed is adjusted by simply altering the front and back sensors' physical
distance to the light curtain.
When the carrier interrupts the front sensor, the sensor sends a negative slope signal to the ObjectC 100
controller. If a light beam in the goods zone (GZ) is interrupted before this signal, an overhang error is detected
and the corresponding output is triggered. The duration of this output signal state can be adjusted with Pot 2.
After the carrier leaves the light curtain it passes through the back sensor. When the carrier no longer interrupts
this sensor it must send a positive slope signal to the ObjectC 100 controller. From then on, if any Object100
goods zone (GZ) beam is interrupted the overhang output will be activated.
Figure 21: Example no overhang
Figure 22: Example Overhang front side
Figure 23: Example Overhang back side
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ObjectC 100
t_ot Allowed
Overhang
duration
t_out Minimum
output duration
t_out Minimum
output
duration
t_out Minimum
output
duration
31