Acquisition Of Speed With Hall Generator - Siemens LMV37.4 Series Basic Documentation

Building Technologies
Speed sensor
Figure 85: Speed sensor
Selection of fan motor
Motor supplier:
Selection of a motor with threaded hole M8 x 15 at the end of the fan motor's drive
shaft.
Standard motor and machining (drilling hole and cutting thread M8 x 15).

12.7.2 Acquisition of speed with Hall generator

If the speed is acquired via a Hall generator, the requirements for safety-related
applications are the same as those for the speed feedback signal via sensor disk.
Required is an asymmetric signal with the 3 pulses of 60°, 120° and 180° for detection
of the direction of rotation.
With the PWM fan, the symmetrical hall signal of the fan can also be used for the
acquisition of motor speed. The symmetry and the number of pulses must be adapted
for this. The maximum speed is 14000 rpm.
No. Parameter
Setting speed signal
0 = asymmetrical
643
1 = symmetrical
644 Number of pulses per rotation (1 to 6)
Basic documentation LMV37.4...
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CC1P7546en
17.12.2018