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Siemens Building Technologies
Basic Documentation RVA63.242, RVA53.242
CE1P2373E
Landis & Staefa Division
Description of heating engineer settings
26.03.2001
Burner control
For the air damper actuator, a switching differential must be set. When the switching
threshold is reached, the air damper actuator is driven be a continuous on or off signal.
It must be made certain that the switching differential for modulation is set small than or
equal to the boiler’s switching differential.
The air damper actuator is controlled in PID mode. By setting the proportional band
(Xp), the integral action time (Tn) and the derivative action time (Tv), the controller can
be matched to the type of plant (controlled system). Also, the air damper actuator
running time is to be set.
For control operation, a neutral zone is used which is at +/- 1K about the current boiler
temperature setpoint. If the boiler temperature stays in the neutral zone for more than
16 seconds, the neutral zone becomes active and positioning pulses are no longer
delivered. As soon as the boiler temperature leaves the neutral zone again, control is
resumed. If the boiler temperature does not stay long enough in the neutral zone,
positioning pulses will also be delivered within the neutral zone.
4.27.4 Cascade with 2 single-stage burners
A cascade is a number of heat sources connected in sequence that, together, deliver
the heat demanded by the heating system. The controller’s cascade is possible with
two single-stage burners.
The burners are connected to burner stage 1 (K4) and burner stage 2 (K5) of the
controller. Multifunctional outputs K6 and K7 are switched as boiler pumps,
independent of their parameterization.
Note assignment:
K4?K6
K5?K7
The functioning for switching the first and second boiler corresponds to that of 2-stage
burner operation.
2-position control
Note
3-position control
Neutral zone
Important