126/267
Building Technologies Basic documentation LMV37.4... CC1P7546en
12 Fan control 17.12.2018
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:
K1
9
5
3
4
+24 V
+
Setpoint 0...10 V
Siemens Micromaster 440
K1
28
Figure 82: 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!
A PWM fan can only be used in the factory settings in conjunction with
pneumatic fuel-air ratio control!
A PWM fan motor can only be used in the electronic fuel-air ratio control system with a
self-regulated PWM fan (see chapter Speed control).
To Next Page
Loading...
Need help?
General
