Modulating Burner, Modulating Output; Two-Stage Burner, 3-Position Output - Siemens RWF40 Series User Manual

5.2.2 Modulating burner, modulating output

5.2.3 Two-stage burner, 3-position output

Landis & Staefa Division
In diagram area (1), the thermostat function is active.
In area (2), the controller is controlling to the adjusted setpoint.
HYS3
W
HYS1
100%
X1
0%
(1)
The positioning signal is delivered as a standard signal via the modulating output.
The modulating controller must be available and configured in the unit (optional).
Section 8.2 «C112 Limit comparator, controller type, setpoint «SP1», locking»
In diagram area (1), the thermostat function is active.
In area (2), a two-position controller acts on the second stage, via relay 2 (open) and
relay 3 (close) by switching it into the circuit at the switch-on threshold «HYS1» / and
out of circuit at the switch-off threshold «HYS2».
HYS3
HYS2
W
HYS1
I
II
(1)
In area (3), the actual value exceeds the upper switch-off threshold «HYS3» and the
controller shuts down the burner (B). The controller only starts low-fire operation when
the level falls below the switch-on level «HYS1» again. If «Q» is exceeded, the
controller switches to high-fire operation (A).
Section 5.6 «Response threshold Q»
CC1B7865E
5. Operating modes
q
A
(2)
B
q
A
(2)
February 10, 2000
B
7865w05/1099
q
A
7865w06/1099
q
A
19/56