Page 97 - Advanced Course

KNX ADVANCED COURSE

1.5.2 Continuous Control with Toggling between Heat and Cool

Figure 11: Control characteristic with two different base values
The continuous control system functions mainly using a PI characteristic. This means that
(in theory) a completely balanced final state is set amongst otherwise fixed parameters,
with a setpoint/actual value deviation of zero. As KNX is a discrete transmission medium,
continual adjustments are not made here but the control variables are recalculated and
sent out at acceptable intervals. When using switching actuators, an approximate
continuous control of an electrothermal drive is achieved via interpulse period modulation.

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