Siemens LMS14

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Building Technologies Division User Manual LMS14… CC1U7471en
6 The settings in detail 28.01.2015
The linear characteristic is defined by 2 fixed points. The setting uses 2 pairs of
parameters for function value and voltage value (F
1/U1 and F2/U2).
Example of 2 different sensor characteristics:
1000 Hz
max
U2 =850 Hz U2 =600 Hz U1 = 50 Hz
2.0 l/min
8.0 l/min
10.0 l/min
U1 = 1Hz
Frequency Hx [Hz]
Water
outlet
[l/min]
Function value
F2 = 100
F2 = 80
F1 = 20
7471d08e/0209
Figure 88: Inputs Hx - Flow measurement Hz
Key
F1 Function value 1
F2 Function value 2
U1 Frequency value 1
U2 Frequency value 2
Line no. Operating line
7862 Frequency H4
 Flow detection DHW (DHW flow switch):
With instantaneous water heater systems, the flow entering the cold water inlet can
be measured with a flow sensor.
A DHW request is identified when the measured flow rate satisfies the following
condition: DHW flow > threshold Tww-FlowSwitch
A DHW request is not identified when the measured flow rate satisfies the following
condition: DHW flow > threshold Tww-FlowSwitch – switching diff.Tww-FlowSwitch
Line no. Operating line
5444 Threshold flow detection
5445 Switching diff flow detection
Line no. Operating line
8860 DHW flow
Frequency value 1
Function value 1
Frequency value 2
Function value 2
Info/diagnostics
A
dditional parameters
Info/diagnostics