Siemens RVA63.242 - Control Action too Fast

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Siemens Building Technologies Basic Documentation RVA53.242, RVA53.242 CE1P2373E
Landis & Staefa Division General control processes 26.03.2001
TKx
2371Z64
t
TKw
Control action of modulating burner too slow
TKx Actual value of the boiler temperature
TKw Boiler temperature setpoint
Procedure
1. Reduce Xp in steps of about 25 % of the previous value.
2.
Reduce Tv in steps of 1 to 2 seconds (if value 0 is reached, the controller
operates as a PI controller)
3. Reduce Tn in steps of 10 to 20 seconds
Repeat steps 2 and 3 alternately.
1.1.2 Control action too fast
If the control system’s response is too “hefty” so that it starts oscillating, setting
parameters Xp, Tn and Tv must be increased in a stepwise fashion. A new
readjustment should be made only after the control action resulting from the previous
readjustment is completed.
TKx
2371Z65
t
TKw
Control action of modulating burner too fast
Procedure
1. Increase Xp in steps of about 25 % of the previous value.
2. Increase Tv in steps of 2 to 5 seconds.
3. Increase Tv in steps of 10 to 20 seconds.
Repeat steps 2 and 3 alternately.
If not sufficient:
If not sufficient: