SMA SC 500HE-US - Manual (Page 38)

7 Active Power Limitation SMA America, LLC
38 SC500HEUS-eng-BE-BUS120320 Operating Manual
7.2.5 "WCnstNom" Procedure
The active power limitation is set as a percentage via the parameter "P-WNom". The percentage value
refers to the parameter "Pmax".
The parameter "P-WNom" indicates the percentage of maximum possible power to be fed in. The
parameter "P-WNom" can be changed during feed-in operation.
7.2.6 "WCnstNomAnIn" Procedure
The active power limitation is set at the input terminals using an analog signal for specifying the target
value (see the inverter installation manual). This is usually implemented by a ripple control receiver.
The electrical current strength of the connected signal determines the rated active power.
The analog measured values must be between 4 mA and 19 mA. If the analog signal is less than
2 mA, the error message will be displayed in the instantaneous value "P-WModFailStt"
(see section 7.4 "Displaying Error Messages and Warnings for Active Power Limitation", page 39).
The analog value is converted to a target value for active power limitation. Here, the parameter
"Pmax" is the end point of the linear characteristic curve.
7.3 Displaying the Active Power Limitation Status
The instantaneous value "P-WModStt" displays the status of the active power limitation.
• Display the instantaneous value " P-WModStt" on the Sunny WebBox user interface
(see section 6.1 "Displaying the Instantaneous Values", page 34).
Parameter used P-WNom
Signal Power limit Description
< 2 mA Last valid value and/or "Pmax"
after restart Signal is in the invalid range.
2 mA … 4 mA 0 kW No power is fed into the grid.
4 mA … 19 mA 0 kW … Pmax Fed-in energy is determined using a
characteristic curve
> 19 mA Pmax Fed-in energy is equal to the value of the
parameter "Pmax".
Parameters used None