PowerManagement covers everything that has to do with influencing the inverters on the part of the energy suppliers.
- Power reduction
- cos PHI (reactive power)
- 70% regulation
In the EnergyMaster, respectively e.manager you can deactivate the ports (RS485 1, LAN, etc.) on which no PowerManagement should be performed on the local web page of the device under Configuration = > Advanced Settings.
At all other interfaces the signals are passed on to the inverters for control (power reduction)!
- Digital input 1: 100%
- Digital input 2: 60%
- Digital input 3: 30%
- Digital input 4: 0%
- If an input is closed, the power is reduced to the specified power.
- If no input is closed the power is set to 100%.
With the "Expert setting" you can combine different switching states, so that a power reduction occurs if e.g. two specific inputs are activated at the same time and not only one.
Please deactivate the Simple setting.
Set the desired input to digital under Configuration = > Configure devices. Assign a unique name, e.g. K1, K2, ...
You can use both the digital inputs and the analog inputs for this purpose.
If you use digital and analog inputs, make sure that they work with different potentials and must therefore be wired separately.
Under Configuration => Power reduction you will now find the activated inputs. Now you can enter up to 10 variants with corresponding percentages.
Check the settings by setting a jumper.
If you operate a PV system with the 70% control, you can increase here a dynamic readjustment of the inverters and an additional increase in self-consumption by connecting consumers.
It is absolutely necessary that the fed-in power can be measured or calculated. For this purpose, the residual feed-in can be measured directly or calculated via the total consumption.
(PV power - total consumption) = Residual feed-in
The residual feed meter or the total consumption meter can be connected via the S0 or D0 interface. You get the best accuracy and updating via D0 counters.
For a control of the PV power, the inverters must be connected to the e.manager via RS485 or LAN and also have the possibility to be controlled steplessly. Prerequisite for a control is the appropriate firmware of the inverters, as well as the implementation of the inverter manufacturer in e.manager. A list can be found on the following page (supported inverters).
When readjusting, the maximum possible inverter power is increased when the inverter power has reached the current maximum power and the fed-in power is below 70%.
Simplified: A 10 kW system feeds in 7 kW (70%).
If there is now the possibility that in-house consumers can use the remaining 3 kW, the inverters receive the command to produce more power, since this excess power is not fed into the public grid.
The increase of the power depends on the current solar irradiation and therefore on the current maximum producible power of the inverters, as well as on the energy consumption of the consumers.
Activate readjustment under self-consumption => settings.
10 kW PV system with 70% control.
- Power limitation 70%
- Consumption is 1kW
- PV power increases to 7kW, feed-in 6kW => Power limitation to 80%
- 1. PV power 8kW, feed 7kW => Power limitation remains at 80%
- 2. an additional consumer is switched on
- PV power 8kW, feed 6kW => 3. power limitation to 90%
- PV power 9kW, feed 7kW => Power limitation remains at 90%
- 4. additional consumer is switched off
- 5. PV power 9kW, feed 8kW => immediate power reduction to 80%
- PV power increases to 7kW, feed-in 6kW => power limitation remains at 80%
- Industrial building
- 500kW installed power
- max. 50kW feed-in
- PV power 450 kW
- own consumption 400 kW
- Feed-in 50 kW
Problem case total failure e.g. of the production line:
- PV power 450 kW
- Own consumption 50 kW
- Feed-in 400 kW
For a few seconds a much too high power is fed in, which could overload the grid.