Balluff BTL7 Series User Manual page 34

BTL7-A/C/E/G501-M _ _ _ _ -P-S32/S115/KA _ _
Magnetostrictive Linear Position Sensor – Profile Style
3
Construction and function (continued)
3.2 Function
The BTL 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 internally 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. Depending
on the version, this information is made available as a
voltage or current with rising or falling gradient.
The following functions can be selected for the output
values:
– Position
– Speed (with or without leading sign)
– Differential position
Two outputs that can be independently assigned are
available. Two magnets can be used.
The entire range of functionality can only be
configured with the PC software BTL7
Configuration Tool. To do this, the USB
communication box must be connected (see
Accessories on page 18).
8 english
3.3 LED display
LED 1 LED 2
Fig. 3-2: BTL7 LED displays
In normal operation, the LEDs indicate the
operating states of the BTL. LED 1 is assigned
to output 1 and LED 2 is assigned to output 2.
LED 1/LED 2 Operating state
Normal function
Green
Magnet is within the limits.
Red Error
No magnet or magnet outside the limits.
Flashing green Programming mode