SMA SC 400HE - Manual (Page 46)

4 Sunny Central Control SMA Solar Technology AG
46 SC4-63HE-BE-BEN103280 Operating Manual
4.7.8 Active Power Limitation Depending on Power Frequency
In addition to the procedures for limiting active power that can be chosen using the "P-WMod"
parameter, active power can be limited depending on the power frequency.
When limiting active power dependent on power frequency, the Sunny Central constantly checks the
connected power frequency.
Figure 15: Behavior of the Sunny Central when exceeding the "P-HzStr" frequency limit
If the power frequency exceeds a certain limit "P-HzStr" defined by you as shown in point A, the
Sunny Central will save the current feed-in power P
cur
. The reduced feed-in power is calculated based
on this saved value. The reduction of the feed-in power is defined through the "P-WGra" parameter.
This parameter indicates by which percentage of the saved power P
cur
output will be reduced per Hz
if the power frequency continues to rise.
If the power frequency decreases again as shown in point B, the last reached feed-in power will
remain valid. Only if the power falls below the "P-HzStop" parameter defined by you as shown in
point C, can the fed-in power be increased again. The saved value "Pcur" will be rendered invalid.
Should the power frequency exceed the power line limit, the Sunny Central will shut down and switch
over to the "Waiting" operating state. The Sunny Central will remain in the "Waiting" operating state
until all feed-in conditions are fulfilled again.
cur