Page 116 of 126
Proton Products SL mini and SLR mini Series Speed and Length Gauges Instruction Manual - issue 1s
APPENDIX 1: HIGH ACCURACY LENGTH MEASUREMENT OF
DISCRETE OBJECTS APPLICATION NOTE
PROBLEM
Length measurement of discrete objects moving on a production line may incur errors due to the
tracking delay / hold time of the SL / SLR / SL mini / SLR mini gauge as individual objects enter and
leave the gauge measurement spot.
SOLUTION
Use two accurately spaced light barriers connected to the logic inputs of the gauge to trigger length
measurement only after the object is in position for accurate speed measurement by the gauge.
One light barrier (LB1) is installed upstream of the gauge and one light barrier (LB2) is installed
downstream of the gauge. “L” is the accurately measured distance between LB1 and LBβ.
The gauge is configured to measure length only when both LB1 and LB2 are interrupted by the
object. The gauge thus measures the length of the object minus a section corresponding to the
distance between LB1 and LB2:
Object length = L + (gauge measured length)
To Next Page
Loading...