A Photo Eye is a versatile object you can use to build logic into your conveyor system. Photo Eyes can also be linked to a Merge Controller to notify it when a released slug has cleared designated points in the system.
For ideas about how to use Photo Eyes to create complex sortation systems or merges, see Flow Control.
Additionally, you could possibly skim through the chapter on Decision Point and Photo Eye Behaviors (Picklists) for more information about some of the Photo Eye's capabilities.
Another difference is that the majority of the settings for a Photo Eye Photo Eye's Type settings. For more information, see:
The previous topic, Photo Eye Type Settings, also has a good explanation of the relationship between Blocked and Cleared states.
Statistics
Photo Eyes track the following statistics. These can be viewed by clicking on a photo eye and then viewing the Statistics pane in Quick Properties.
- Content The number of items that have covered the photo eye but have not yet cleared it. This is usually either 0 or 1, but if the photo eye has an offset angle, it may be greater than 1.
- Input The total number of items that have covered the photo eye.
- Output The total number of items that have cleared the photo eye.
- State The photo eye tracks state using two different state profiles, namely the default state profile, and a custom "PhotoEye" state profile. The custom profile uses the following states:
- Clear The photo eye is completely clear.
- Blocking The photo eye was covered from a Clear state, but its Block Time has not yet expired.
- Blocked The photo eye is covered and its Block Time has expired.
- Clearing The photo eye was uncovered from a Blocked state, but its Clear Time has not yet expired.
For the default state profile, it uses the following states:
- Idle The idle state corresponds to the Clear plus Blocking states in the photo eye's custom state profile.
- Blocked The blocked state corresponds to the Blocked plus Clearing states in the photo eye's custom state profile.
