Samson 5100, 5179 5.3Fixed set point control, Functions of the heating circuit

Functions of the heating circuit

Note!

The 4-point characteristic function can only be activated when the Adaptation function is not active (Co1, 2, 3 -> Fb07 = OFF).

5.3Fixed set point control

During the times-of-use, the flow temperature can be controlled according to a fixed set point. Outside the times-of-use, this set point is reduced by the Set-back difference. Both Minimum flow temperature and Maximum flow temperature parameters are set to identical values.

Parameters	WE	Parameter level / Range of values
Max. flow temperature	90 °C	PA1, 2, 3	/ 20 to 130 °C
Min. flow temperature	20 °C	PA1, 2, 3	/ 20 to 130 °C
Set-back difference	20 °C	PA1, 2, 3	/ 0 to 50 °C

5.4Differential temperature control using variable weighting factors

This function allows the return flow temperature to be taken into account in addition to the flow temperature. It can only be used in heating circuits with mixing valves.

The difference between the flow and return flow temperature is specified using the Intended temperature difference parameter. It is a measure for the energy consumption in a heating cir- cuit. The greater the temperature difference, the larger the energy required by a heating circuit. If the actual temperature difference is not the same as the intended temperature difference, it is evaluated by the Kp factor for differential temperature control. After initial signs for a deviation occur, the flow temperature is raised or reduced by this factor.

When the Kp factor for differential temperature control is set to 0, the return flow temperature does not have any affect on the control of the flow temperature.

When the Kp factor for differential temperature control is set to 1, a pure return flow tempera- ture limitation takes place (–> section 7.4).

The reset time TN determines how fast the deviation of the temperature difference affects the control circuit (the larger TN is, the slower the rate in change).

The Intended temperature difference parameter is maintained at a constant value by adjusting the speed of the associated circulation pump in the heating circuit. The pump is controlled by an analog 0 to 10 V signal, which is applied to the associated analog output (AA) of the controller (AA1 to AA3). The control signal is displayed in the associated info level. When the differential temperature control without return flow limitation is active, the actual temperature of the return flow is nevertheless displayed. After pressing the enter key, the set point is displayed together with the string "S-r" (for differential temperature control using variable weighting factors).

42EB 5179 EN