External Load Controller Via Analog Input X64 Pin 1 / X64 Pin 2; Switching Thresholds For Modulating Operation - Siemens LMV37.4 Series Basic Documentation

Switching thresholds /
minimum positioning
step
100/267
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9.6 External load controller via analog input X64
pin 1 / X64 pin 2
For the preselection of external outputs, an analog 4...20 mA input is provided.
Burner startup can take place only when contact X5-03 pin 1 is closed (load controller
ON / OFF).
A disruption of the current input or a current signal <3 mA leads to deactivation of the
analog input's external predefined output.
The behavior of the LMV37.4 in the event of an invalid analog input can be defined.
To avoid unnecessary positioning steps of the actuators when the input signal varies, it
is possible to set a minimum positioning step for the predefined output. The minimum
positioning step only becomes active in modulating operation. For the external load
controller via the analog input, a value of 1% is preset.
No. Parameter
123.1 Minimum output positioning step: Output external load controller analog
Behavior if analog input is invalid (4...20 mA)
0 = deactivate default output low-fire / trim function (with warning message)
204
1 = safety shutdown + startup prevention
2 = deactivate default output low-fire / trim function (without warning message)
GND
Figure 73: External load controller via analog input X64 pin 1 / X64 pin 2

9.6.1 Switching thresholds for modulating operation

Actual value
Low-fire
Low-fire
High-fire
Basic documentation LMV37.4...
9 Connection to load controllers
LMV...
PWM fan
5
4
3
2
1
Bild 364e/0409
Current
3...4 mA
4 mA
20 mA
Display / output value
20%
20%
100%
CC1P7546en
17.12.2018