SMA SC 500CP-US-10 600V - Manual (Page 58)

8 Reactive Power Control SMA America, LLC
58 SCCP-US-BE-US_en-52 Operating Manual
The analog value is converted into a reactive power setpoint. The electrical current strength of the connected signal
determines the setpoint.
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 Q-VArModFailStt instantaneous value.
The analog value is converted to a setpoint for power limitation. Here, the parameter Pmax is the end point of the linear
characteristic curve.
Figure 22: Limiting the parameter Pmax to the parameter Qmax
If the value of Pmax exceeds the value of Qmax, the characteristic curve of the value Q
max
will be limited to Qmax
and the reactive power value in the range from +Q
max
to +P
max
will remain constant at Qmax.
If the value of ‒Pmax falls below the value of ‒Qmax, the characteristic curve of the value ‒Q
max
will be limited to
‒Qmax and the reactive power value in the range from ‒Q
max
to ‒P
max
will remain constant at ‒Qmax.
Signal Power limit Description
< 2 mA Last valid value or 0 kVAr
after restart
Signal is in the invalid range.
2 mA to 4 mA − Pmax The maximum amount of negatively excited reactive power is fed in.
4 mA − Pmax Starting point of the characteristic curve
Maximum amount of negatively excited reactive power is fed in.
11.5 mA 0 kVAr Zero-crossing of the characteristic curve
No reactive power is fed in.
> 19 mA +Pmax End point of the characteristic curve
Maximum amount of positively excited reactive power is fed in.
Parameters used none