Speed Control - Siemens LMV37.4 Series Basic Documentation

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Building Technologies Division
Industry Sector

12.8 Speed control

The LMV37.4... controls the fan motor's speed to the setpoint. To ensure that the speed
can still be increased when the maximum speed is reached, the speed is standardized
when the motor is controlled at 95%. Hence, with a speed setpoint of 100 %, a speed
increase of 5 % is still possible.
The control range of the LMV37.4... is +15% / -10%. If this range is not sufficient, error
80 or 83 can occur.
Error Diagnostic code
code
80 1
2
Note
Internal control with a VSD or PWM fan motor must not be activated. Otherwise,
speed variations can occur, resulting from simultaneous control actions from both the
basic unit and internal control.
Basic documentation LMV37.4...
12 Fan control
Meaning for the LMV37.4... system
Control range limitation at the bottom
Control range limitation at the top
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CC1P7546en
20.09.2013