FLB Series • Frame Light Barriers Product Information
info@sensorinstruments.de • www.sensorinstruments.de
(2003-05-22) FLB Series / Page 1 of 4
Sensor Instruments GmbH • D-94169 Thurmansbang • Schlinding 11
Tel. +49 (0)8544 9719-0 • Fax +49 (0)8544 9719-13
Characteristics
Operative range
The frame light barriers of FLB Series are used for the measurement
of smallest unguided parts. In addition, some types feature an analog
output which, among other things, can be used for positioning or for
strip width monitoring. This analog signal is monitored with the electronic
control unit FLB-CON2, and an error signal is generated if the measured
value rises above or falls below the set tolerances.
The frame light barriers of FLB Series are extremely insensitive to
outside light due to optical filtering and modulated operation. Still
they guarantee safe measurement of parts with sizes starting from
only 0.2 mm. An impact protection facility (aluminum baffle plates,
rubber-metal vibration dampers) protects the optical unit of the frame
light barrier against impacting parts.
With its compact design and with the remote control unit (in case of
FLB-FR3) this type of frame light barrier is excellently suited for eject
monitoring in a punching die, for example.
High sensitivity due to threshold correction
By continuously monitoring the maximum value at the receiver a
dynamic switching threshold correction compensates the effect of dirt
accumulation. Increasing dirt accumulation therefore does not lead to
change of sensitivity.
Example:
The switching threshold (sensitivity) is set to 50% of the maximum value.
After increased dirt accumulation the switching threshold still is 50%.
This means that the sensitivity does not change.
Parameterisable under Windows® (FLB-CON2)
With the FLB-CON2
sensor parameters such as tolerance, reference,
switching hysteresis, bright/dark switching, and pulse lengthening can
be set through the RS232 interface by means of Windows® software
FLB/TLB-Scope. In addition the analog signal or the tolerance band,
respectively, are graphically displayed at the PC.
Functional principle
The optoelectronic components of the transmitter and receiver units are
arranged opposite to each other in the frame (in the sides in case of fork
or split design). Both the transmitter and the receiver unit consist of a
row of IR transmitter diodes or phototransistors, which form a homogeneous
light curtain between the transmitter and receiver unit.
If a measuring object now passes through this light curtain, part of the
light band is covered, and less IR light thus impinges on the receiver
unit. The signal generated by the phototransistors is then attenuated
and differentiated proportional to the impinging quantity of light, and the
differentiated signal is sent to a comparator pulse lengthening unit.
FLB Series
Product Information
The
sensors of FLB Series detect parts starting from
a size of 0.2 mm with a switching frequency of 1 kHz.
An additional analog output (0...+10V) offers application
possibilities in the field of measuring technology.
With the electronic control unit FLB-CON2 an
operator-friendly parameterisation on a PC under
Windows® is ensured.
Increase of dirt accumulation Time (hrs)
Voltage (V)
0 5 10 15
5.0
10.0
20 25 30 35
Analog signal
(light barrier uncovered)
50% 50%
Corrected threshold
50% 50%
50% 50%
50% 50%
50% 50%
50% 50%
