Three-point controller Hys.

This function block implements a three-point controller. This controller has, instead of switch-on/switch-off limits, a setpoint with adjustable hysteresis.

Inputs
FU	Enable AU	Enable output AU. The output is enabled when 1 is present at the input. This input is optional; if the input is not connected, the output is automatically enabled.
FO	Enable AO	Enable output AO. The output is enabled when 1 is present at the input. This input is optional; if the input is not connected, the output is automatically enabled.
IW	Actual value	Actual value
SW	Setpoint	Setpoint. If the actual value falls below the setpoint minus hysteresis, the lower output is switched on; if the actual value exceeds the setpoint plus hysteresis, the upper output is switched on.
HY	Hysteresis	Hysteresis. The hysteresis acts in half each on the lower and upper switching threshold.
Outputs
A1		Description

Parameters
	Control time	Control time in seconds. The setpoint / actual value comparison is only performed at this interval.
	Temperature monitoring minimum	Optional temperature monitoring. If the actual value falls below this limit, the output ST Temperature fault is set to 1 and the outputs are switched off. If both limit values are 0, the monitoring is not active.
	Temperature monitoring maximum	Optional temperature monitoring. If the actual value exceeds this limit, the output ST Temperature fault is set to 1 and the outputs are switched off. If both limit values are 0, the monitoring is not active.

See also common parameters of all function blocks.