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BTS-Ex, non-contacting thermal switch unit
Function of BTS-Ex
2.4 Interaction of BTS-Ex components
Instead of a blind screw, the switching element is screwed into the turbo coupling. The
initiator with mounting flange is mounted parallel with the turbo coupling axis and is
connected to the evaluator.
The coil inside the switching element is coupled inductively with the coil inside the
initiator if the switching element is located in front of the initiator head. When the
thermostatic switch is closed, energy is transmitted from the initiator to the switching
element. The oscillator is attenuated and has a lower current consumption.
If the coupling temperature exceeds the response temperature of switching element,
the thermostatic switch will interrupt the circuit in the switching element. The switching
element can no longer attenuate the oscillator in the initiator.
The evaluator recognizes the attenuation of initiator due to the initiator current con-
sumption.
If the turbo coupling with screwed in switching element rotates, then the switching ele-
ment will permanently pass the initiator, thus permanently creating attenuation pulses.
Thus, permanently attenuation pulses are generated. The output relay in the evaluator
is energized.
In case of excess temperature, these attenuation pulses are not given, i.e. the cutoff
frequency set on the evaluator is not reached. The evaluator recognizes the missing
pulses, the output relay is de-energized.
Installation, position
Chapter 6.3
Cutoff frequency
Chapter 3.3