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Siemens Building Technologies
Basic Documentation RVP540 / RVP550
CE1P2488en
HVAC Products
Description of the heating engineer settings
18.10.2002
The controller is given the pump speed nP [%] as the target variable (setpoint). For that
purpose, the controller converts the PWM signal (PWM %) in a way that, based on the
following graph, it corresponds to the pump speed to be reached. This converted signal
is available at the terminal.
[%]
0
20
40
60
80
100
10
20
30
40
50
60
70
80
90 100
[%]
23
92Z
4
4
0
nP
PWM
8%
89%
The controller wants the pump to run at 45 % of its nominal speed. For that purpose, it
delivers a PWM signal of 52.5 %.
The PWM characteristic is specific to the pump manufacturer. The characteristic shown
above represents the mean value of the most common products.
4.264 PWM signal logic P1
•
Invertible
PWM
signal
The PWM signal can be inverted. This means that it is also possible to control variable
speed pumps with an inverted signal logic.
Setting range
Unit
Factory setting
0...1 –
0
The selected signal logic will automatically be displayed on this operating line.
0 Standard
The signal will not be inverted (corresponds to the PWM characteristic).
1 Inverted
The signal will be inverted before it is delivered.
PWM output
Example:
Note
Benefit
Description
Setting
Effect
