The PI1 optical limit switch features an infrared photointerrupter to detect position when a blade crossed the gap. The datasheet for the Rohm Semiconductor RPI-441C1E is available here.

The RPI-441C1E is small but features a large 4mm gap. The circuit is built to provide a logic HIGH at detection, with visual LED feedback. The 3-pin connector (Signal, Power, Ground) is mounted outside the travel path of the blade. For maximum mounting flexibility, the PI1 is available with various connector mount configurations:

• No connector. For DIY applications. The user will supply the connector or solder the wires directly to the connector holes.
• Right angle pins on Top (same side as the sensor)
• Right angle pins at Bottom
• JST connector on Top. This option includes a keyed female JST with 20cm pigtail.
• JST connector at Bottom. This option includes a keyed female JST with 20cm pigtail.

Note: Multiple PI1 cannot connect to a single limit input since the inactive sensor will prevent the active signal from going HIGH. The PI1 requires a dedicated input, such as the F46.