Vsd Control X74 Pin 3; Pwm Fan Control X64 Pin 3 - Siemens LMV37.4 Series Basic Documentation

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12.3 VSD control X74 pin 3

The VSD is controlled via a voltage interface (refer to chapter Load output X74 pin 3)!
Depending on the type of VSD used, a release contact is required. This contact can be
controlled via the fan motor contactor. To enable the VSD to bring the fan motor's speed
to the correct no-load speed, the motor contactor's drop out delay time must be about
25 seconds.
Example:
Siemens Micromaster 440
9
+24 V
5
3
+
Setpoint 0...10 V
4
28
Figure 73: Connection of VSD to the LMV37.4...
It is possible to set the VSD control to 0 via the analog output when the safety loop is
open (including burner flange switch).
This may be necessary if the no-load speed is not 0.
No. Parameter
652 VSD behavior when safety loop / burner flange is open
0 = no VSD control when safety loop / burner flange is open
1 = VSD control independent of safety loop / burner flange

12.4 PWM fan control X64 pin 3

The PWM fan is controlled via PWM voltage interface X64 pin 3.
Caution!
The use of PWM fans is only possible in connection with pneumatic air-fuel
ratio control!
Basic documentation LMV37.4...
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CC1P7546en
20.09.2013