Technical reference and worked-example guide
Photo-fork sensor learning guide: field reference
Direct answer
The reader can match the throat geometry, response time and output interface to the target, then isolate alignment, contamination, wiring and timing faults.
Written for automation learners and technicians detecting labels, slots, edges and small passing parts with a transmitter and receiver in one fork housing.
Definition
Target width and thickness, fork gap, insertion depth, edge position, contrast, speed, response frequency, light or dark operation, output type, wiring, contamination and mounting.
Signal path
Part movement through beam interruption, receiver decision, transistor output, PLC channel, program state and independently observed part position.
Worked example
Every representative part produces one stable transition at the declared position and line speed.
Limits
Transparent or reflective target, partial insertion, vibration, dust, beam chatter, excess speed, reversed logic, lost supply and restart.
Common mistake
A target, geometry, optical, mounting, response-time, output, wiring, input-filter or program mismatch.
Verification
The chosen unit proved across production tolerances with the actual mounting and PLC input.
What is a fork photoelectric sensor?
It places an optical transmitter and receiver across a fixed slot, detecting an object or edge when it changes the light path through that slot.
Why does a fork sensor miss labels at speed?
Response frequency, label geometry, gap, vibration, contamination, output timing or PLC input filtering may be too slow or unstable for the passing target.