Pwm Fan Control X64 Pin 3; Safe Separation Of Mains Voltage And Protective Extra Low-Voltage; Ramp Time - Siemens LMV36.520A1 Basic Documentation

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For VSD operation
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13.4 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!
13.5 Safe separation of mains voltage and
protective extra low-voltage
Caution!
All inputs and outputs of PWM fan control are designed for use with protective
extra low-voltage. For this reason, strict separation from the mains voltage side
must be ensured!
This necessitates an external power supply by the VSD or an external power pack (X74
pin 1, X74 pin 2).
Note
Power must also be supplied via X74 pin 1 / pin 2 in the case a PWM fan is used.

13.6 Ramp time

The ramp time for fan control can be set separately for acceleration and deceleration
(also refer to chapter Traveling speed/maximum curve slope).
No. Parameter
522 Ramp up
523 Ramp down
544 Ramp modulating
If shutdown occurs because the speed has not been reached, the VSD/fan motor might
not be able to follow quickly enough the set ramp.
In the case of a ramp time >20 seconds, the modulating operating ramp (parameter
544) must be increased (refer to chapter Running speed / maximum curve slope).
Remedy:
Shorten further the ramp of the VSD/fan motor or increase the ramp in the basic unit
(parameters 522/523) (also refer to chapter Traveling speed/maximum curve slope).
Caution!
The ramps parameterized for the VSD should be at least 20% shorter than the
ramps in the LMV36...
Example:
5 s ramp LMV36...
10 s ramp LMV36...
20 s ramp LMV36...
40 s ramp LMV36...
Basic documentation LMV36...
13 Fan control
4 s ramp VSD
8 s ramp VSD
16 s ramp VSD
32 s ramp VSD
CC1P7544en
25.09.2013