Banner L-GAGE LT7 Series - Manual (Page 4)

L-GAGE® LT7 Long-Range Time-of-Flight Sensor
Banner Engineering Corp. • Minneapolis, MN U.S.A
www.bannerengineering.com • Tel: 763.544.3164
4
P/N 120244 Rev. B
Theory of Operation
A short electrical pulse drives a semiconductor laser diode to emit a pulse of light. The
emitted light is collimated through a lens, which produces a very narrow laser beam.
The laser beam bounces off the target, scattering some of its light through the sensor’s
receiving lens to a photodiode, which creates an electrical pulse. The time interval
between the two electrical pulses (transmitting and receiving the beam) is used to
calculate the distance to the target, using the speed of light as a constant.
Multiple pulses are evaluated by the sensor’s microprocessor, which calculates the
appropriate position value. The outputs energize whenever the target is located between
the user-programmed window limits or when the preset switching threshold is crossed.
Outputs may be programmed for a variety of functions.
Figure 6. Theory of operation
Mode Q1
Teach-In
(Set Q1)
Teach 1.1 Teach 1.2 Hyst 1
Teach-In
(Setup)
Mode Q2
Teach-In
(Set Q2)
Teach 2.1 Teach 2.2 Hyst 2 Mode Analog
Teach-In
Analog
Copy Q>A Teach A1 Teach A2
Q1 Q2
QuickSet
(Enter)
4564 mm
Q1 |||| q2
Factory
(Preset)
Run Mode
Main Menu
Factory > OK
RS422
(see page 13)
Unit
(MM)
Unit > mm Unit > inch
Password
(OFF)
Password (OFF) Password (ON)
Serial
(RS422)
Serial > SSI Serial > Ext. Bus* Serial > RS422
Password (Required only
if Password option is ON.
Factory preset is Password
OFF.
• Visible Pilot Laser OFF.
• Measuring Laser ON.
• Press or to
light display backlight
• Visible Pilot Laser ON.
• Measuring Laser ON.
• Display backlight ON.
Use or to scroll
between Main Menu
selections.
Use or to
scroll between
selections.
or or or
or
or
Offset
(0)
Offset nnnn Offset > clear?
or or or or
*Ext. Bus requires specialized sensor; not currently available.
Output 1
Menu
Output 2
Menu
Analog Output
Menu
Figure 7. Programming menu tree
Microprocessor
User
Interface
Emitter
Circuitry
Analog
Signal
Processing
Time-of-Flight
Engine
Output
Circuitry
Laser
Emitter
Lenses Target
Receiver
Element
E
R