Balluff BTL7-A5-M Series, User Manual

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Fig. 3-1:
48.8 70.5 82
69
100 %
100 % 0 %
0 %
0 %
Ø 54.5
Ø 43.6
Ø 31
Ø 10.2
2
BTL7…-SF-F…, construction
3.1 Construction
Electrical connection:
The electrical connection is made
via a cable (see Type code on page 22).
Housing: Stainless steel housing containing the
processing electronics.
Float: Defines the position to be measured on the
waveguide. Order floats separately (see Accessories on
page 20).
Nominal length:
Defines the travel/length range available.
Rods with various nominal stroke lengths from 50 mm to
2500 mm are available depending on the BTL version.
3.2 Function
The BTL contains the waveguide which is protected by an
outer stainless steel tube (rod). A float is moved along the
waveguide. This float also rises and falls with the level of
the liquid whose position is to be determined.
The float defines the position to be measured on the
waveguide.
An internally generated INIT pulse interacts with the
magnetic field of the float 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 a 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 position is
determined from the propagation time of the wave.
Depending on the version, this information is made
available as a voltage or current with rising or falling
gradient.
3
Construction and function
BTL housing
Float
1)
BTL-S-3112-4Z
Output with falling gradient
Output with rising gradient
Nominal length = measuring range
Cotter pin
1)
1) Not included in scope of delivery
Tank full Tank empty
BTL7-A/C/E5 _ _ -M _ _ _ _ -SF-F _ _
Magnetostrictive Linear Position Sensor – Rod Style