Balluff BTL7-P511-M P-S32 Series, Руководство пользователя

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3
Construction and function (continued)
3.2 Function
The BTL7 transducer contains the waveguide which is
protected by an aluminum housing. A magnet is moved
along the waveguide. This magnet is connected to the
system part whose position is to be determined. The magnet
defines the position to be measured on the waveguide.
An externally generated INIT pulse interacts with the
magnetic field of the magnet to generate a torsional wave
in the waveguide which propagates at ultrasonic velocity.
The component of the torsional wave which arrives at the
end of the waveguide is absorbed in the damping zone to
prevent reflection. The component of the torsional wave
which arrives at the beginning of the waveguide is
converted by a coil into an electrical signal. The travel time
of the wave is used to calculate the position. The position
value corresponds to the travel time of the torsional wave
and is output as digital time information between the start
and stop pulses.
The evaluation may relate to the rising or falling edge. This is
done with a high level of precision and reproducibility within
the measuring range indicated as the nominal length.
Fig. 3-2:
T
T
Start Stop
Init
Time/distance measuring principle
3.3 Number of magnets
Up to 16 magnets can be used. The distance (L) between
the magnets must be at least 65 mm.
Fig. 3-3:
L L L
Distance between the magnets
3.4 LED display
Fig. 3-4:
LED 2 LED 1
BTL7 LED displays
LED 1
Green
Normal function
Magnet is within the limits.
Red Error
No magnet or magnet outside the limits.
LED 2
Off
Normal function
Valid Init signal.
Flashing red
Init error
Missing or invalid Init signal and LED 1 is off.
BTL7-P511 -M _ _ _ _ -P-S32/S115/KA_ _
Micropulse Transducer in a Profile Housing