SMA SC 500CP-US-10 600V - Manual (Page 57)

SMA America, LLC 8 Reactive Power Control
Operating Manual SCCP-US-BE-US_en-52 57
Reactive Power Control Procedure and Setting Associated Parameters
1. Ensure that the inverter is in the "Stop" operating state.
2. Log in to the user interface.
3. Enter the password in the appropriate field on the homepage and confirm with [Login].
4. Change the parameter Q-VarMod (see Section 6.2 "Changing Parameters", page 51).
5. Change parameters belonging to the selected procedure.
8.1.1 Off Procedure
The reactive power setpoint is limited to 0 kVAr. This target value cannot be influenced.
8.1.2 VArCtlCom Procedure
The reactive power target value is received by the SC-COM via Modbus and then transmitted to the inverter. The setpoint
is detected as a percentage and converted to kVAr within the inverter.
If the inverter has received no signal for five minutes, the error message in the Q-VArModFailStt instantaneous value
will be displayed.
8.1.3 PFCtlCom Procedure
The reactive power target value is received by the SC-COM via Modbus and then transmitted to the inverter. A
displacement power factor cos φ is transmitted as a target value.
If the inverter has received no signal for five minutes, the error message in the Q-VArModFailStt instantaneous value
will be displayed.
8.1.4 VArCnst Procedure
The parameter Q-VAr is used to set the reactive power setpoint in kVAr. The Q-VAr parameter may be within the range
‒Qmax to +Qmax.
8.1.5 VArCnstNom Procedure
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.
8.1.6 VArCnstNomAnln Procedure
The reactive power setpoint is set at the input terminals via an analog signal for specifying the setpoint (see Sunny Central
installation manual). This is usually accomplished via a ripple control receiver.
Parameter blocking
The parameter Q-VARMod may only be changed in the "Stop" operating state. The entry will not be accepted in
other operating states.
Parameters used none
Parameters used none
Parameters used none
Parameter used Q-VAr
Parameter used Q-VArNom