Overview Block Energy Manager



Function block for the energy management of a house with photovoltaics. The main consumers are the heat pump (heating), the charging station (wallbox) and a continuously controlled heating element for domestic hot water preparation. The block belongs to the control element Block Energy Manager and must be connected with it.

The generated or exported PV surplus is distributed in the following priority order:
  1. Heating via the heat pump (highest priority)
  2. Charging station (wallbox)
  3. PV heating element for domestic hot water preparation
Heating (heat pump): The heating always has priority and is controlled via the outputs Heating enable and Heating setback. When the setback is active, the heating maintains the (lower) setpoint temperature specified at the input. If sufficient generated PV power is available (setpoint PV threshold heating, default 2 kW), the heat pump is enabled. If power is actually exported to the grid, the setback is lifted so that the house is slightly overheated with the surplus. If the room temperature falls below the minimum temperature room (default 21 °C), the heating is always enabled - with setback - even without PV. When the room temperature reaches the maximum temperature room (default 24 °C), the setback is switched back on and the overheating is ended.

Charging station (wallbox): The charging station is enabled as soon as more than the setpoint charging power minimum (default 4 kW) is exported to the grid. After that the outputs Wallbox enable and Wallbox power kW are output and the charging power is controlled so that the surplus is used up, limited to charging power minimum/maximum (default 4 / 15 kW). The heating retains priority, since the grid export already accounts for the consumption of the heat pump.

PV heating element hot water: The continuously controlled heating element uses the remaining export for domestic hot water preparation, as long as the hot water temperature is below the setpoint temperature PV (default 65 °C). It is controlled so that a small export reserve (setpoint grid minimum, default 0.8 kW) is maintained, so that heating and wallbox retain priority. In manual mode (On) it heats to the setpoint temperature manual (default 45 °C). If the hot water temperature falls below the minimum temperature (default 40 °C), it is heated at 100 % regardless of the PV surplus (frost protection).

Switch-on delay: All three consumers have a switch-on delay of 5 minutes: the respective enable condition must be present continuously for that long before it is enabled. This avoids frequent on/off switching with short load changes or cloud gaps. The cold protection of the heating (room temperature below minimum temperature) bridges the delay and enables immediately.

The setpoints and the operating mode per consumer (Automatic / On / Off) are defined in the settings of the control element (see Setpoints).

Tip: Variables must be connected at the used inputs and outputs, since they are needed for control and for the display on the control element.


Inputs

BA
 Operating mode
 General operating mode. The operating mode of the individual consumers (heat pump, wallbox, heating element) is defined in the settings of the control element.
LN
 Grid power kW
 Grid power. Positive means draw from the grid, negative means feed-in (export). This value is the basis for the enabling of the wallbox, the control of the heating element and the lifting of the heating setback.
LP
 PV power kW
 Currently generated PV power. Used for the enabling of the heat pump (not the export).
LP
 Charging station power kW
 Current charging power of the charging station. Serves as feedback for the power control of the wallbox.
BL
 Battery power kW
 Optional if a battery is present. Used for the calculation of consumption and self-sufficiency. Depending on the input battery status, subtracted when charging and added when discharging.
BA
 Battery charge %
 Optional if a battery is present. Current charge state of the battery in percent (display on the control element).
BS
 Battery status
 Optional if a battery is present. Defines whether the battery is charging or discharging. Which value corresponds to charging or discharging is set in the parameters Battery status charging/discharging.
TR
 Temperature room
 Current room temperature. Controls the enabling of the heat pump (cold protection) and the setback (minimum/maximum temperature room).
TW
 Temperature hot water
 Current hot water temperature. Controls the PV heating element (setpoint, manual and minimum temperature).

Outputs
VB
 Consumption kW
 Current consumption. Calculated internally from PV power and grid power (with a battery present, including battery power).
AT
 Self-sufficiency %
 Self-sufficiency in percent. Share of self-generated of the total consumed energy.
HF
 Heating enable
 Enable of the heat pump. 1 when sufficient generated PV power is available or the room temperature is below the minimum temperature (cold protection). A switch-on delay of 5 minutes applies, which is bridged by the cold protection.
HA
 Heating setback
 Setback of the heating. 1 = setback active, the heating maintains the setpoint temperature specified at the input. 0 = setback lifted, the house is slightly overheated with the PV surplus. The setback is only lifted as long as power is exported to the grid; from the maximum temperature room or below the minimum temperature room the setback is always active.
HW
 Heating hot water
 Provided for hot water preparation via the heat pump. Currently not driven (remains 0); the PV hot water preparation is done via the output Hot water auxiliary heating.
WZ
 Hot water auxiliary heating
 Continuous setpoint 0-100 % for the PV heating element. Uses the remaining PV surplus as long as the hot water temperature is below the setpoint temperature. With minimum temperature protection (frost protection) and manual mode. A switch-on delay of 5 minutes applies.
WF
 Wallbox enable
 Enable of the charging station. 1 when, for longer than the switch-on delay (5 minutes), more than the charging power minimum (default 4 kW) is exported to the grid.
WL
 Wallbox power kW
 Setpoint of the charging power. Controlled so that the PV surplus is used up, limited to charging power minimum/maximum.

Parameters
Battery status charging
 Value at the input battery status when the battery is charging.
Battery status discharging
 Value at the input battery status when the battery is discharging.

Setpoints (settings in the control element)
Operating mode heat pump / heating element / wallbox
 Operating mode per consumer: 0=Automatic, 1=On, 2=Off. Default Automatic.
Minimum temperature room
 Below this room temperature the heating is always enabled with setback (cold protection). Default 21 °C.
Maximum temperature room
 From this room temperature the setback is always switched on, the overheating is ended. Default 24 °C.
PV threshold heating
 Generated PV power from which the heat pump is enabled. Default 2000 W.
Setpoint temperature PV (hot water)
 Maximum temperature hot water for the PV heating element. Default 65 °C.
Setpoint temperature manual (hot water)
 Setpoint temperature of the heating element in manual mode (On). Default 45 °C.
Minimum temperature hot water
 Below this hot water temperature the heating element is operated at 100 % regardless of the PV surplus (frost protection, 1 °C hysteresis). Default 40 °C.
Charging power minimum
 Export threshold for enabling the wallbox and at the same time minimum charging power. Default 4000 W.
Charging power maximum
 Maximum charging power of the wallbox. Default 15000 W.
Grid minimum (export reserve)
 Export reserve that the heating element receives, so that heating and wallbox retain priority. At the same time serves as a threshold for lifting the heating setback. Default 800 W.

See also common parameters of all function blocks.