SMA 1000-1SC, Системное руководство

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13.3.2.5 Active Power Limitation via Standard Signal: WCnstNomAnIn Mode
The active power limitation is set via an analog signal at the input terminals for the setpoint. This is usually implemented
by a ripple control signal. The electrical current strength of the connected signal determines the nominal active power.
The analog measured values must be between 4 mA and 19 mA. If the analog signal is less than 2 mA, an error
message will be displayed in the instantaneous value
P-WModFailStt .
Signal Power limit Description
< 2 mA Last valid value or Pmax after restart Signal is in the invalid range.
2 mA to 4 mA 0 kW No power is fed into the grid.
4 mA to 19 mA 0 kW to Pmax The energy fed into the grid is determined by a character-
istic curve.
> 19 mA Pmax The energy fed into the grid equals Pmax .
The analog value is converted to a setpoint for power limitation. Here, the parameter Pmax forms the end point of the
linear characteristic curve.
13.3.3 Reactive Power Control
13.3.3.1 No Reactive Power Control: Off Mode
The reactive power setpoint is limited to 0 kVAr. This setpoint cannot be controlled.
13.3.3.2 Reactive Power Control with Setpoint Command via Modbus Protocol:
VArCtlCom Mode
The reactive power setpoint is received by the communication unit and transmitted to the inverter. The setpoint is
transmitted as a percentage value and converted to kVAr in the device. If the inverter has not received any signal for
five minutes, the error message
Q-VArModFailStt will be displayed.
13.3.3.3 Reactive Power Control with Setpoint Command via Modbus Protocol:
PFCtlCom Mode
The reactive power setpoint is received by the communication unit and transmitted to the inverter. The setpoint is
transmitted as a displacement power factor cos φ. If the inverter has not received any signal for the last five minutes, an
error message will be displayed in the instantaneous value
Q-VArModFailStt .
13.3.3.4 Reactive Power Control with Absolute Value: VArCnst Mode
The reactive power setpoint is set via the parameter Q-VAr . The parameter Q-VAr is permitted to be within the range
from ‒Qmax to +Qmax .
13.3.3.5 Reactive Power Control as a Percentage of the Nominal Power: VArCnstNom
Mode
The parameter Q-VArNom is used to set the reactive power setpoint in %. The parameter Q-VArNom refers to
Pmax . If the calculated amount of reactive power exceeds the predefined value of Qmax , the power will be limited
to Qmax . If the calculated amount of reactive power falls below the predefined value of ‒Qmax , the power will be
limited to ‒Qmax .
13 Function Description SMA Solar Technology AG
System Manual MVPS22JP-SH-en-11 192