Solare Datensysteme Solar-Log - Manual (Page 137)

137
Special functions
Note
The 70% reduction is always applied to the entire plant.
All of the inverters are controlled on the same level by the Solar-Log™, independent of
their alignments (east-west orientation). This can lead to a lower feed-in amount than
the maximum allowed.
Example 1
DC power 12 kWp
AC power 12 kW
70% of the DC power corresponds to 8.4kW
As the AC and DC power are identical, the down-control is correct.
Example 2
DC power 12 kWp
AC power 10kW
70% of the DC power corresponds to 8.4kW
For this reason the inverter controlled by the Solar Log™ is reduced to 84% (8.4kW) and not only to 70%
(7kW).
23�2�7 70% Fixed reduction with the calculation of self-consumption
This function is an enhancement to the 70% fixed reduction described in the previous chapter.
The Solar-Log™ needs to be linked to a consumption meter to implement this function. Please note the
instructions in chapter”12.5 External power meter”.
The configuration of this corresponds to that already described for the 70% fixed reduction.
Procedure
•
Select 70% Fixed reduction with the calculation of self-consumption
•
Select the interface of the inverter that is to be reduced
•
SAVE settings.
Note
The Solar-Log™ needs to be linked to a consumption meter to implement this function.
Please note the instructions in chapter”12.5 External power meter”.
The current amount of self-consumption is calculated by employing a power meter for self-consumption.
The consumption is calculated with the energy generated by the inverter.
If the difference between the current production and consumption is lower than 70% of the module‘s
power output, the inverters are regulated accordingly, so that the amount of power at the feeding point is
still only at 70% of the connected generator power.