SMA SC 500HE-20 - Manual (Page 50)

6 Setpoint for Active Power and Reactive Power SMA Solar Technology AG
50 SCxxxHE-20-BE-BEN111210 Operating Manual
6.2.8 "PFCnst" Procedure
The reactive power setpoint is set using the "PF-PF" and "PF-PFExt" parameters. The "PF-PF" parameters
indicate the displacement power factor cos φ and the "PF-PFExt" parameter indicates the degree of
excitation. Here, the "PFAbsMin" parameter is the start and end point of the linear characteristic curve.
6.2.9 "PFCnstAnIn" Procedure
The reactive power target value is set at the input terminals using an analog signal for specifying the
target value (see enclosed installation manual). This is usually accomplished by using a radio ripple
control receiver.
The analog value is converted into a power factor. The current of the connected signal determines the
target value.
The analog measured values must be between 4 mA … 19 mA. If the analog signal is smaller than
2 mA, the error message in the "Q-VarModFailStt" spot value will be displayed.
The analog value is converted to the power factor target value. Here, the "PFAbsMin" parameter is
the start and end point of the linear characteristic curve.
Used parameters PF-PF
PF-PFExt
Signal Power limit Description
< 2 mA Last valid value or 1 after restart Signal is in the invalid range.
2 mA … 4 mA PFAbsMin / underexcited The maximum amount of
negatively excited reactive
power is fed in.
4 mA PFAbsMin / underexcited Starting point of the curve
Maximum amount of negatively
excited reactive power is fed in.
11.5 mA 1 Zero-crossing of the curve
No reactive power is fed in.
> 19 mA PFAbsMin / overexcited End point of the curve
Maximum amount of positively
excited reactive power is fed in.
Used parameters PFAbsMin